Seto no Hanayome

Seto no Hanayome (瀬戸の花嫁) is the title of a Japanese manga series written by Tahiko Kimura. The manga was first serialized in 2002 in the Japanese manga magazine Monthly Gangan WING, published by Square Enix. In 2004, a drama CD based on the series was released by Frontier Works. An anime television series adaptation animated by Gonzo and directed by Seiji Kishi aired in Japan on TV Tokyo between April 1 and September 30, 2007, containing twenty-six episodes. An original video animation project has also been announced. Odex, a Singaporean distributor, released it in English in Singapore as Seto No Hana Yome. The anime was licensed for a North American distribution by Funimation Entertainment and will be titled My Bride is a Mermaid!.

Plot
The story of Seto no Hanayome revolves around a young teenage boy named Nagasumi Michishio. One day during his summer vacation at Seto Bay, Nagasumi is saved from drowning by a mermaid, Sun Seto. Under mermaid law, however, either the mermaid whose identity was revealed, or the human who saw the mermaid, must be executed. In an attempt to save both Nagasumi and Sun's lives, Sun's family, which is the head of a mermaid mafia group, reluctantly decides that the two are to be married. Sun's father Gōzaburō is enraged about his daughter's sudden marriage. Between Gōzaburō's constant attempts on his life and the madcap antics of a slew of antagonists, Nagasumi has a hard time transitioning into his new married lifestyle.

Characters
Some mermaid/merman characters are named for star (or planet) names and sea names.

Michishio family

 * Nagasumi Michishio (満潮 永澄)
 * Nagasumi is the main character of the story. Nagasumi is likely the only one in his family who has a clear head, apart from his grandmother. When push comes to shove, Nagasumi demonstrates a great deal of inner strength. He decided to face his fears and take on the responsibility of taking care of Sun as his wife, although it doesn't make it easy on him due to almost everyone in the Seto group (except Sun's mother—Ren, and Masa) who are against their union. As the series progresses, however, he truly falls in love with Sun. Sun often uses her Song of Heroes to power Nagasumi up in battle situations, but in the case where Sun is directly threatened he is able to activate the power-up by himself.
 * Nagasumi is the main character of the story. Nagasumi is likely the only one in his family who has a clear head, apart from his grandmother. When push comes to shove, Nagasumi demonstrates a great deal of inner strength. He decided to face his fears and take on the responsibility of taking care of Sun as his wife, although it doesn't make it easy on him due to almost everyone in the Seto group (except Sun's mother—Ren, and Masa) who are against their union. As the series progresses, however, he truly falls in love with Sun. Sun often uses her Song of Heroes to power Nagasumi up in battle situations, but in the case where Sun is directly threatened he is able to activate the power-up by himself.


 * Nagasumi's father (永澄の父)
 * Nagasumi's father is always shown as an object of suffering, due to his wife's dying love for him. Whenever his wife shows her interest in Masa, he is shown in a depressed state, like the time she offers Masa her home cooked meal, he is shown coughing on a burger and then subsequently harangued by his boss to get back to work.
 * Nagasumi's father is always shown as an object of suffering, due to his wife's dying love for him. Whenever his wife shows her interest in Masa, he is shown in a depressed state, like the time she offers Masa her home cooked meal, he is shown coughing on a burger and then subsequently harangued by his boss to get back to work.


 * Nagasumi's mother (永澄の母)
 * Nagasumi's mother is the easy going type, and has an interest for Masa, which her husband is not particularly happy about. Current events in her life have caused her love towards her husband to gradually die out.
 * Nagasumi's mother is the easy going type, and has an interest for Masa, which her husband is not particularly happy about. Current events in her life have caused her love towards her husband to gradually die out.


 * Nagasumi's grandmother (永澄の祖母)
 * She makes an appearance early in the story and allows Nagasumi to stay at her house during their stay with her.
 * She makes an appearance early in the story and allows Nagasumi to stay at her house during their stay with her.

Seto family

 * Sun Seto (瀬戸 燦)
 * The female protagonist of the story, Sun is the daughter of the Yakuza Seto Group's boss, Gōzaburō Seto. She is a firm believer in the chivalrous spirit of mermaids, and is devoted to her role as Nagasumi's wife. She is also in love with Nagasumi. Since she has yet to become an adult, Sun is unable to completely maintain her human form, and her legs revert to a tail whenever she comes into contact with water. She often cites the similarity between the Japanese words "ninkyō" (任侠) and "ningyo" (人魚) to stress her adherence to honorable courses of action. When Sun enters chivalry mode cherry blossom petals can be seen in the background. It is later revealed during Lunar and Nagasumi's wedding that if the need arises she can fight very well with a sword and also shows behavior much like a Yakuza member. Her name is related to Seto Inland Sea and is a direct reference to the Sun. She has her own personal body guards but does not use them same way that Lunar does. They only show up on matters involving Lunar’s personal body guards whom they (Sun's body guards) are constantly at war with. Like most mermaids, she has a fear of cats (ailurophobia), but is capable of getting over it on occasion, like when the kitten that lives in Nagasumi's house is in danger of drowning, and she goes to save it.
 * The female protagonist of the story, Sun is the daughter of the Yakuza Seto Group's boss, Gōzaburō Seto. She is a firm believer in the chivalrous spirit of mermaids, and is devoted to her role as Nagasumi's wife. She is also in love with Nagasumi. Since she has yet to become an adult, Sun is unable to completely maintain her human form, and her legs revert to a tail whenever she comes into contact with water. She often cites the similarity between the Japanese words "ninkyō" (任侠) and "ningyo" (人魚) to stress her adherence to honorable courses of action. When Sun enters chivalry mode cherry blossom petals can be seen in the background. It is later revealed during Lunar and Nagasumi's wedding that if the need arises she can fight very well with a sword and also shows behavior much like a Yakuza member. Her name is related to Seto Inland Sea and is a direct reference to the Sun. She has her own personal body guards but does not use them same way that Lunar does. They only show up on matters involving Lunar’s personal body guards whom they (Sun's body guards) are constantly at war with. Like most mermaids, she has a fear of cats (ailurophobia), but is capable of getting over it on occasion, like when the kitten that lives in Nagasumi's house is in danger of drowning, and she goes to save it.


 * Gōzaburō Seto (瀬戸 豪三郎)
 * Gōzaburō is the boss of the Seto Group. He dotes on his daughter and hates Nagasumi for, as he sees it, trying to steal her away. By pulling strings at the ministry of education, Gōzaburō, together with many of the Seto Group members, enrolls in the staff of Nagasumi's junior-high school in order to watch over Sun, thus becoming Nagasumi and Sun's homeroom teacher. Even though he is the Yakuza head of the Seto group as well as a powerfully built man with a formidable attitude, he has an overwhelming fear of cats (or kittens) due to an incident that happened in his childhood (which parodies that of Doraemon's fear of mice, both in its origins and his reaction when seeing the object of his phobia). He fears his wife as she will not hesitate to hand out punishment.
 * Gōzaburō is the boss of the Seto Group. He dotes on his daughter and hates Nagasumi for, as he sees it, trying to steal her away. By pulling strings at the ministry of education, Gōzaburō, together with many of the Seto Group members, enrolls in the staff of Nagasumi's junior-high school in order to watch over Sun, thus becoming Nagasumi and Sun's homeroom teacher. Even though he is the Yakuza head of the Seto group as well as a powerfully built man with a formidable attitude, he has an overwhelming fear of cats (or kittens) due to an incident that happened in his childhood (which parodies that of Doraemon's fear of mice, both in its origins and his reaction when seeing the object of his phobia). He fears his wife as she will not hesitate to hand out punishment.


 * Ren Seto (瀬戸 蓮)
 * Ren is Sun's mother. She likes to encourage Sun and Nagasumi, The most feared member of the Seto Group she usually tries to keep her husband and any other Seto Group members in check, often handing out extreme forms of punishment if they step out of line and has the final say on all matters. She also enjoys teasing Nagasumi, whom she thinks to be cute. She transfers with several other members of the Seto Group to Nagasumi's school, becoming the new school nurse. Like her daughter Sun When Ren enters chivalry mode pink flower petals can be seen in the background. Ren on appearance is seen as a kind and gentle person but shows behaviour much like a Yakuza member. Her name is likely a reference to the mythical creature, the Siren.
 * Ren is Sun's mother. She likes to encourage Sun and Nagasumi, The most feared member of the Seto Group she usually tries to keep her husband and any other Seto Group members in check, often handing out extreme forms of punishment if they step out of line and has the final say on all matters. She also enjoys teasing Nagasumi, whom she thinks to be cute. She transfers with several other members of the Seto Group to Nagasumi's school, becoming the new school nurse. Like her daughter Sun When Ren enters chivalry mode pink flower petals can be seen in the background. Ren on appearance is seen as a kind and gentle person but shows behaviour much like a Yakuza member. Her name is likely a reference to the mythical creature, the Siren.

Seto Group members

 * Masa (政)
 * Masa is a member of the Seto Group. He has an afro and always wearing sunglasses. Masa is the one who, through performing CPR, "stole" Nagasumi's first kiss. He also transfers to Nagasumi's school, becoming his math teacher (whose word problems tend to describe to the mathematical aspects of underworld gang operations). There is a running gag of Nagasumi displaying an attraction towards Masa since their 'first kiss' in the first episode. Masa is the only one apart from Sun's mother who doesn't object to the engagement and sometimes even gives advice to Nagasumi. Usually he is portrayed a silent man. However, when he drinks he tends to talk too much and reminisce. He is revealed later in the series to be the long-lost brother of Shiranui Akeno. Masa cares a lot for his sister Shiranui Akeno and is very protective of her often beating up those who are aggressive towards her. Masa is one of the few Merfolk not afraid of cats, explaining that he decided to overcome the fear as a child.
 * Masa is a member of the Seto Group. He has an afro and always wearing sunglasses. Masa is the one who, through performing CPR, "stole" Nagasumi's first kiss. He also transfers to Nagasumi's school, becoming his math teacher (whose word problems tend to describe to the mathematical aspects of underworld gang operations). There is a running gag of Nagasumi displaying an attraction towards Masa since their 'first kiss' in the first episode. Masa is the only one apart from Sun's mother who doesn't object to the engagement and sometimes even gives advice to Nagasumi. Usually he is portrayed a silent man. However, when he drinks he tends to talk too much and reminisce. He is revealed later in the series to be the long-lost brother of Shiranui Akeno. Masa cares a lot for his sister Shiranui Akeno and is very protective of her often beating up those who are aggressive towards her. Masa is one of the few Merfolk not afraid of cats, explaining that he decided to overcome the fear as a child.


 * Maki (巻)
 * "Spiral Shell" Maki, despite being only few inches tall, is an assassin working for the Seto Group, as well a devoted friend of Sun. She uses a shell to shoot water balls as fast and powerful bullets and has a seemingly unlimited supply of ammunition. She, like Gōzaburō, dislikes the idea of "losing" Sun to Nagasumi, and will often distract Sun with sweet talk in order to fire her shell gun at Nagasumi. She thinks that Nagasumi and Lunar would be a much better match. She has a fear of cats (ailurophobia), but much to her dismay the cat at the Nagasumi's house has a liking to Maki and is often seen around her when Maki is not with Sun.
 * "Spiral Shell" Maki, despite being only few inches tall, is an assassin working for the Seto Group, as well a devoted friend of Sun. She uses a shell to shoot water balls as fast and powerful bullets and has a seemingly unlimited supply of ammunition. She, like Gōzaburō, dislikes the idea of "losing" Sun to Nagasumi, and will often distract Sun with sweet talk in order to fire her shell gun at Nagasumi. She thinks that Nagasumi and Lunar would be a much better match. She has a fear of cats (ailurophobia), but much to her dismay the cat at the Nagasumi's house has a liking to Maki and is often seen around her when Maki is not with Sun.


 * Shark Fujishiro (シャーク藤代)
 * Shark is a member of Seto Group initially summoned by Sun's father during the Michishio family's initial visit to the Seto family home to attack Nagasumi. In human form, he later becomes Nagasumi's P.E. teacher. By his thinking, the sooner Nagasumi dies, the sooner everyone can return home.  He often acts on this logic, trying to eat him. According to him, the answer to all problems is by eating the person causing the chaos, be it Sun's or Lunar's fans or a suicide bomber from his own group. he often seen sleeping and unlike Kai Mikawa he has the ability to only transform his head into that of a shark while his legs remain human.
 * Shark is a member of Seto Group initially summoned by Sun's father during the Michishio family's initial visit to the Seto family home to attack Nagasumi. In human form, he later becomes Nagasumi's P.E. teacher. By his thinking, the sooner Nagasumi dies, the sooner everyone can return home.  He often acts on this logic, trying to eat him. According to him, the answer to all problems is by eating the person causing the chaos, be it Sun's or Lunar's fans or a suicide bomber from his own group. he often seen sleeping and unlike Kai Mikawa he has the ability to only transform his head into that of a shark while his legs remain human.


 * Octopus Nakajima (オクトパス中島)
 * Nakajima is another member of the Seto Group and is actually an octopus. He too becomes a teacher at Nagasumi's school. Unlike the others, his human form is never shown in the entire anime. Most of the time he appears stuck inside the school due to his huge size. It's also shown that some of his tentacles are missing. Some scenes taking place in the cafeteria will show octopus being fed to the students.
 * Nakajima is another member of the Seto Group and is actually an octopus. He too becomes a teacher at Nagasumi's school. Unlike the others, his human form is never shown in the entire anime. Most of the time he appears stuck inside the school due to his huge size. It's also shown that some of his tentacles are missing. Some scenes taking place in the cafeteria will show octopus being fed to the students.

Edomae family

 * Lunar Edomae (江戸前 留奈)
 * Lunar is a childhood friend and rival of Sun. She has used the powers of her mermaid voice to become an idol singer. She seems to suffer from a superiority complex, and she never passes up an attempt to overshadow Sun. She initially thought that Sun was boasting Nagasumi to her, and in an attempt to outdo Sun she decides to steal him away from her by making Nagasumi her servant, since Nagasumi has also seen her mermaid form.  Later she decides to live in Nagasumi's house until his servant status is over. It was unclear if she has developed a liking to him (since she has decided to learn how to cook and make him a packed lunch, although still in an attempt to beat Sun). However, it is then revealed that she does in fact have feelings for Nagasumi, and planned on marrying him, but this is stopped by Sun. Even after her wedding was canceled she continued living with Nagasumi. Lunar controls her own personal body guards made up of the boys of Isono Junior High school, she often calls them in to defend her. She uses her personal body guards like her own personal army. They are currently at war with Sun’s body guards. Lunar has a trademark "hohoho" laugh that can be heard before she enters the scene; she has a fear of cats (ailurophobia).
 * Lunar is a childhood friend and rival of Sun. She has used the powers of her mermaid voice to become an idol singer. She seems to suffer from a superiority complex, and she never passes up an attempt to overshadow Sun. She initially thought that Sun was boasting Nagasumi to her, and in an attempt to outdo Sun she decides to steal him away from her by making Nagasumi her servant, since Nagasumi has also seen her mermaid form.  Later she decides to live in Nagasumi's house until his servant status is over. It was unclear if she has developed a liking to him (since she has decided to learn how to cook and make him a packed lunch, although still in an attempt to beat Sun). However, it is then revealed that she does in fact have feelings for Nagasumi, and planned on marrying him, but this is stopped by Sun. Even after her wedding was canceled she continued living with Nagasumi. Lunar controls her own personal body guards made up of the boys of Isono Junior High school, she often calls them in to defend her. She uses her personal body guards like her own personal army. They are currently at war with Sun’s body guards. Lunar has a trademark "hohoho" laugh that can be heard before she enters the scene; she has a fear of cats (ailurophobia).


 * Lunar's Papa (ルナパパ)
 * Never referred to as anything but Lunar's Papa, he is Lunar's father and leader of the Edomae group (in which whereas the Seto group's holdings are in business, the Edomae group focuses in construction and real estate). He is two meters tall and constantly dressed in a black skintight suit. Lunar's Papa is a man of very few words and is modeled after the Terminator.  He is an extremely well built man (though in the manga he looks more thin), a point of humor in the show due to his body sounding like metal when hit.  His actions are often direct references to the Terminator movies, such as sinking into an incinerator giving a thumbs up while even saying in English "I'll be back". His appearance theme is a parody of the lead music score from the Terminator movie 'Judgment Day'. Despite his cold and unemotional appearance, he cares very much for his daughter. He does everything he can for her, though discretely so.  He is also extremely rich, as evidenced in one episode of using 10 billion dollars US (in cash) to keep the production of a film Lunar is acting in going.  In the final episode, he is revealed to have laser eye beams. He is often seen in female sailor’s uniform which Lunar hates, he also has influence in the ministry of education able to get into Nagasumi's school pretending to be a middle school student so he could get closer to Lunar.
 * Never referred to as anything but Lunar's Papa, he is Lunar's father and leader of the Edomae group (in which whereas the Seto group's holdings are in business, the Edomae group focuses in construction and real estate). He is two meters tall and constantly dressed in a black skintight suit. Lunar's Papa is a man of very few words and is modeled after the Terminator.  He is an extremely well built man (though in the manga he looks more thin), a point of humor in the show due to his body sounding like metal when hit.  His actions are often direct references to the Terminator movies, such as sinking into an incinerator giving a thumbs up while even saying in English "I'll be back". His appearance theme is a parody of the lead music score from the Terminator movie 'Judgment Day'. Despite his cold and unemotional appearance, he cares very much for his daughter. He does everything he can for her, though discretely so.  He is also extremely rich, as evidenced in one episode of using 10 billion dollars US (in cash) to keep the production of a film Lunar is acting in going.  In the final episode, he is revealed to have laser eye beams. He is often seen in female sailor’s uniform which Lunar hates, he also has influence in the ministry of education able to get into Nagasumi's school pretending to be a middle school student so he could get closer to Lunar.


 * Amano Sagami (相模　天王)
 * Lunar's mother and Lunar's Papa's ex-wife. She left the two when Lunar was five years old.

Others

 * Mawari Zenigata (銭形 巡)
 * Mawari is the daughter of the chief of police in Nagasumi's hometown, and a childhood friend of Nagasumi, whom she has a crush on. She takes it upon herself to act as a moderator of social behavior, and often reprimands Nagasumi for some of his actions. Mawari's dream is to become a police chief like her father. Nagasumi say her personality is like Sun which shocks Sun. Her name is related to Zenigata Heiji and "Omawari-san" (a gentle and polite way to say policeman in Japanese). One thing of interest is that whenever Mawari speaks or does something related to peacekeeping, whistling (like that of a police whistle) can be heard in the background. She is referred to as the queen of cards at Isumo elementary school due to her having won two championships at the Isumo elementary school first year student’s card game tournament with Nagasumi as her partner. She is a member of the disciplinary committee and is the leader of the Public Morals Committee/Peacemakers which is a group formed by the girls of Isono Junior High School; the group is Isono Junior High's Police and is the biggest of the three groups, they can take on both Sun and Luner's group at once, they are at war with both Sun and Lunar's personal body guards. Due to Mawari’s police background she is able to see through the lies that any of her school member make, she often gets close to finding out the fact that Sun is a mermaid but gets stopped by Nagasumi before she does. She also has a trade mark line “Do You Want Mawari to Teach You the Rules of the Society” she says this when people break her rules.
 * Mawari is the daughter of the chief of police in Nagasumi's hometown, and a childhood friend of Nagasumi, whom she has a crush on. She takes it upon herself to act as a moderator of social behavior, and often reprimands Nagasumi for some of his actions. Mawari's dream is to become a police chief like her father. Nagasumi say her personality is like Sun which shocks Sun. Her name is related to Zenigata Heiji and "Omawari-san" (a gentle and polite way to say policeman in Japanese). One thing of interest is that whenever Mawari speaks or does something related to peacekeeping, whistling (like that of a police whistle) can be heard in the background. She is referred to as the queen of cards at Isumo elementary school due to her having won two championships at the Isumo elementary school first year student’s card game tournament with Nagasumi as her partner. She is a member of the disciplinary committee and is the leader of the Public Morals Committee/Peacemakers which is a group formed by the girls of Isono Junior High School; the group is Isono Junior High's Police and is the biggest of the three groups, they can take on both Sun and Luner's group at once, they are at war with both Sun and Lunar's personal body guards. Due to Mawari’s police background she is able to see through the lies that any of her school member make, she often gets close to finding out the fact that Sun is a mermaid but gets stopped by Nagasumi before she does. She also has a trade mark line “Do You Want Mawari to Teach You the Rules of the Society” she says this when people break her rules.


 * Hideyoshi Sarutobi (猿飛 秀吉)
 * Hideyoshi Sarutobi, often referred to as Saru (or Chimp in the English dub), is a friend of Nagasumi who is often portrayed as a perverted monkey (a pun on his name; "saru" meaning monkey). He later became Kai's "servant" and always protects and helps him when he is in need. In the beginning, Saru's reasons for befriending Kai are because of his fortune; However, in episode 24 it is shown Saru genuinely cares for Kai. His name is related to Sarutobi Sasuke and Toyotomi Hideyoshi (Who himself was also often called "Saru/Monkey"). Saru occasionally appears dressed as an old hermit, "ero-sennin" (erotic/perverted thousand-year-old), who periodically appears to offer insights of perverted sagacity, When in the old hermit form he calls himself "Saru Roshi" a parody of Master Roshi from Dragon Ball.
 * Hideyoshi Sarutobi, often referred to as Saru (or Chimp in the English dub), is a friend of Nagasumi who is often portrayed as a perverted monkey (a pun on his name; "saru" meaning monkey). He later became Kai's "servant" and always protects and helps him when he is in need. In the beginning, Saru's reasons for befriending Kai are because of his fortune; However, in episode 24 it is shown Saru genuinely cares for Kai. His name is related to Sarutobi Sasuke and Toyotomi Hideyoshi (Who himself was also often called "Saru/Monkey"). Saru occasionally appears dressed as an old hermit, "ero-sennin" (erotic/perverted thousand-year-old), who periodically appears to offer insights of perverted sagacity, When in the old hermit form he calls himself "Saru Roshi" a parody of Master Roshi from Dragon Ball.


 * Class President (委員長)
 * She is a good friend of Mawari and a meganekko. While her true name is unknown, her classmates only refer her as the Class President. Despite the fact that she is the class president, her presence is usually too passive to be noticeable. She later reveals that she has very strong feelings for Nagasumi. Later, she writes a love letter to Nagasumi, to confess her love, but accidentally confesses to Sun due to not looking at the person she was confessing to. This event leads to the sudden creation of an alternate persona, the "Last Amazoness", a girl-loving warrior who declares her intent to have Sun as her own. The Class President uses this persona when she's trying to get noticed or when she needs extra confidence. In recent volumes of the manga, the Last Amazoness takes an active role in fighting troublemakers after receiving a gender-reversing mermaid weapon, "Gender-X", from Surtan. The Class President also works with Maki on occasion, believing her to be a fairy, her desire is for people to find out her real name.
 * She is a good friend of Mawari and a meganekko. While her true name is unknown, her classmates only refer her as the Class President. Despite the fact that she is the class president, her presence is usually too passive to be noticeable. She later reveals that she has very strong feelings for Nagasumi. Later, she writes a love letter to Nagasumi, to confess her love, but accidentally confesses to Sun due to not looking at the person she was confessing to. This event leads to the sudden creation of an alternate persona, the "Last Amazoness", a girl-loving warrior who declares her intent to have Sun as her own. The Class President uses this persona when she's trying to get noticed or when she needs extra confidence. In recent volumes of the manga, the Last Amazoness takes an active role in fighting troublemakers after receiving a gender-reversing mermaid weapon, "Gender-X", from Surtan. The Class President also works with Maki on occasion, believing her to be a fairy, her desire is for people to find out her real name.


 * Kai Mikawa (三河 海)
 * Kai is the richest boy in Japan, the fourteen-year-old son of the head of the multi-million dollar Mikawa Corporation. He rivals Nagasumi for Sun's hand in marriage. He is a killer whale from another mermaid group. Strangely while Sun and Lunar are shown in Mermaid form (torso of a human and tail of a fish) whenever they fail to maintain their human forms, Mikawa is shown as an entire killer whale when he succumbs to the effect of water. He also has agoraphobia, which is why he travels only in submarines and wears an astronaut's suit in open spaces. While looking for a servant he befriends Saru. His name is related to Mikawa Bay and Neptune (海王星). Kai- like most merfolk- has a fear of cats (ailurophobia). He is usually seen in a Japanese navy uniform and carrying a katana. He is the leader of Sun's bodyguard.
 * Kai is the richest boy in Japan, the fourteen-year-old son of the head of the multi-million dollar Mikawa Corporation. He rivals Nagasumi for Sun's hand in marriage. He is a killer whale from another mermaid group. Strangely while Sun and Lunar are shown in Mermaid form (torso of a human and tail of a fish) whenever they fail to maintain their human forms, Mikawa is shown as an entire killer whale when he succumbs to the effect of water. He also has agoraphobia, which is why he travels only in submarines and wears an astronaut's suit in open spaces. While looking for a servant he befriends Saru. His name is related to Mikawa Bay and Neptune (海王星). Kai- like most merfolk- has a fear of cats (ailurophobia). He is usually seen in a Japanese navy uniform and carrying a katana. He is the leader of Sun's bodyguard.


 * Akeno Shiranui (不知火 明乃 明星)
 * Akeno is not only a mermaid but also a "mermaid examiner". She has the responsibility of deporting all the mer-people who fail to qualify as not only resembling humans but also not arousing any suspicion of their true identities. When first introduced she had a hostile attitude towards the other major protagonists. This later changes as develops feelings of compassion towards them and also as she finds her "duty" as a Knight-in-training as an excuse used by the final antagonist. It is also revealed that she is, in fact, Masa's younger sister, a fact which she is unaware of. Her name is related to Shiranui Sea and Venus (明けの明星). She is terrified of ghosts and is hinted that she has feelings for Nagasumi.
 * Akeno is not only a mermaid but also a "mermaid examiner". She has the responsibility of deporting all the mer-people who fail to qualify as not only resembling humans but also not arousing any suspicion of their true identities. When first introduced she had a hostile attitude towards the other major protagonists. This later changes as develops feelings of compassion towards them and also as she finds her "duty" as a Knight-in-training as an excuse used by the final antagonist. It is also revealed that she is, in fact, Masa's younger sister, a fact which she is unaware of. Her name is related to Shiranui Sea and Venus (明けの明星). She is terrified of ghosts and is hinted that she has feelings for Nagasumi.


 * Satori Sarutobi (猿飛 悟)
 * Saru's little sister who appears in the original manga and the OVA series. After being saved from a burning movie theatre by Nagasumi, she calls him "Nagasumi Willis" after "Bunta Willis" an action hero that parodies Bruce Willis and Bunta Sugawara. She develops feelings for Nagasumi.
 * Saru's little sister who appears in the original manga and the OVA series. After being saved from a burning movie theatre by Nagasumi, she calls him "Nagasumi Willis" after "Bunta Willis" an action hero that parodies Bruce Willis and Bunta Sugawara. She develops feelings for Nagasumi.


 * Surtan (サーたん)
 * A childhood friend of Sun, Surtan is a seaweed creature whose hair allows her to cling to ceilings and entangles on objects in the water. Her hair can act as weapon to strangle opponent, and sometimes unwillingly trap a lot of things usually find in water, from fish to sea garbage, even a person. Lack of water is something she can't handle. She becomes an English teacher at Sun's junior high school in volume nine of the manga. She appeared in the second OVA (Gi).
 * A childhood friend of Sun, Surtan is a seaweed creature whose hair allows her to cling to ceilings and entangles on objects in the water. Her hair can act as weapon to strangle opponent, and sometimes unwillingly trap a lot of things usually find in water, from fish to sea garbage, even a person. Lack of water is something she can't handle. She becomes an English teacher at Sun's junior high school in volume nine of the manga. She appeared in the second OVA (Gi).


 * Yuhiteru Suruga (駿河 由比輝)
 * Alias: Jupiter. Member of the Weapon Attack Team and executive officer at Isono Junior High school. Jupiter is a friend of Akeno whom she refers to as "Onee-sama" and has romantic feelings for.


 * Fuki (蕗)
 * Maki's younger sister. Uses a fuki leaf instead of a shell for her attacks. Fuki is the bodyguard of Maruko.


 * Maruko Okhotsk (緒呆突 丸子)
 * Yet another childhood friend of Sun.

Manga
The Seto no Hanayome manga series started serialization in 2002 in the Japanese manga magazine Monthly Gangan WING published by Square Enix. As of March 2008, fourteen bound volumes have gone on sale in Japan and the manga is currently unfinished. As of May 2009, Seto no Hanayome will end serialization in Gangan WING and will be subsequently published in Monthly Gangan Joker.

Anime
The animated TV series adaptation directed by Seiji Kishi and produced by Gonzo and AIC aired in Japan on TV Tokyo between April 1 and September 30, 2007, containing twenty-six episodes. Episode seventeen of the anime adaptation scheduled for broadcast on the Japanese cable network Anime Theater X on September 3, 2007 was canceled due to concerns of copyright infringement. Some of the characters who appear in that episode are believed to closely resemble characters from other works.

Three pieces of theme music were used for the anime: one opening theme, and two ending themes. The opening theme is "Romantic Summer" by Sun (Haruko Momoi) & Lunar (Sakura Nogawa), which was written, composed, and arranged by Halko Momoi. In the opening video, the characters dancing behind Sun change depending on the episode whether it is dedicated or related to them (for example, Nagasumi dancing with the Seto's Special Squad brothers). The first ending theme, used for episodes one through thirteen, and then again for episode twenty-six, is "Asu e no Hikari" (明日への光) by Asuka Hinoi, which was written, composed, and arranged by Yugo Sasakura. In the video, the image in the ending changes slightly between each episode as new characters are introduced in the anime. The second ending theme, used for episodes fourteen through twenty-five, is "Dan Dan Dan" by Sun (Haruko Momoi) & Lunar (Sakura Nogawa), which was written by Gorō Matsui, and composed and arranged by Shūhei Naruse. In the video, the characters' animations change depending on the circumstances they undergo during the episode (for example, the Class President transforming into "Yes! Amazoness!").

The series was licensed by Funimation Entertainment and was released under the title My Bride is a Mermaid!. The first of two parts was released on July 20, 2010.

OVA
A two-episode original video animation entitled Jin (仁) was released on November 28, 2008, along with the OVA ending theme single, "Mirai e Go" (未来へGo). The OVA's opening theme single, "Zettai Otome" (絶対乙女), was released on October 29, 2008. A second OVA entitled Gi (義) was released on January 30, 2009, along with its ending theme, "Kakehashi" (梯 -かけはし-). The opening theme for this OVA, "Tenshi Ranman Love Power" (天使爛漫 Love Power), was released on December 24, 2008.