Nyan Koi!

Nyan Koi! (にゃんこい!) is a manga created by Sato Fujiwara. It started serialization on Flex Comix's free web comic FlexComix Blood on August 10, 2007. An anime adaptation premiered on October 1, 2009 in Japan. A second season for the anime was announced at the end of the 12th episode of the first season.

Plot
Junpei Kōsaka is a second-year high school student who despises cats and has an allergy to them. It just so happens that his high school crush is Kaede Mizuno, a girl who adores cats. One day, while walking home from school, Junpei kicks an empty can and unfortunately breaks the local neko-jizō-sama (guardian deity of cats). He finds he can now understand what cats are saying, including his family’s own ill-tempered cat, Nyamsus. However, if he does not grant 100 wishes to cats, he will turn into a cat himself and die from his own allergy.

Human Characters

 * Junpei Kōsaka (高坂 潤平)

The main protagonist who has a chronic allergy to cats. He lives with his mother and sister, however, who love them (which does not help his predicament). To complicate matters, he accidentally destroys the statue of a cat deity, and to compensate for it, he must make use of his new-found ability of communicating with cats to fulfill one hundred requests of help from them without letting other people know that he is cursed or he will be transformed into one. Ironically, everyone around him seems to love cats. He has feelings for Kaede Mizuno.
 * Kaede Mizuno (水野 楓)

Junpei's classmate and crush who is totally oblivious of his feelings for her (though she realizes feelings for him as time passes). She is described as athletic, smart and cute. Despite loving cats, her family owns four dogs, and cats tend to avoid her as she always carries their smell. She tends to be air-headed, react to things naively and misunderstand people. Kaede met Junpei when she fell on him from out of a tree trying to rescue a kitten that later climbed down itself.
 * Kanako Sumiyoshi (住吉 加奈子)

She is one of Junpei's classmates and his childhood friend. During elementary school, the two became enemies due to a misunderstanding where Kanoko thought that Junpei was giving away her gift to another girl while in fact he was only showing it to her. Due to her unhappiness from being at odds with Junpei, she takes on a Manba appearance at first, but dresses normally after returning to friendly terms with him. Kanako is often seen bickering with Junpei and has a short-temper. She has a well-endowed body, and isn't afraid to flaunt it, but often gets unwanted attention and teased from Ichinose's hands. Sumiyoshi is very forceful and often gets Junpei to purchase her food at his own expense. She still harbors feelings for him.
 * Nagi Ichinose (一ノ瀬 凪)

Kaede's senior on the track team and heir of a powerful Yakuza family from Kyoto. Despite being a girl, she started assuming a more masculine behavior after she was rejected by her first love, who mistakenly assumed she was a guy because of her boyish appearances. However after Junpei comforts her, she fell for him and resorts to extreme actions to be beside him, like attempting to move to his class despite having already coursed it. She suffers from astraphobia, the fear having stemmed from the fact that she was traumatized from seeing her grand father getting struck by lightning on several occasions in front of her. She also graces her sudden appearances by sexually harassing Sumiyoshi (often involving grabbing her breasts). She has a rare condition where she gets drunk just by drinking soft drinks.
 * Kotone Kirishima (桐島 琴音)

She is the twin sister of Akari and the older of the two. She, along with her sister, are the daughters of the Buddhist monk in the temple. Despite her gentle and sweet outward demeanor, she is interested in Junpei mainly because of his misfortunes, and can be considered sadistic, delusional, and an obsessive stalker. In the anime, she is shown to have this sort of behaviour even at a young age towards a teacher. She also shows jealousy if another girl gets too close to Junpei.
 * Akari Kirishima (桐島 朱莉)

She is the twin sister of Kotone and the younger of the two. She, along with her sister, know that Junpei is cursed. They do not become cursed as they have innate anti-magic abilities, but only for self protection. She is tsundere, and has the ability to sense the supernatural. In the anime, Akari was said to not socialize much even at a young age, thus causing her awkwardness when it comes to dealing with people. The reason for this is because of her strong spiritual affinity, and she subconsciously avoided mixing around with other children. She is also shown to have magical powers (though this is not the case in the manga). She is extremely possessive of Kotone; besides her twin sister, she seems to show no problem interacting with Junpei (though mostly for her mistaken perception that he's becoming too close to Kotone) like she does with most other people.
 * Keizou Kirishima (桐島 啓造)

He is the Buddhist monk in the temple wherein the cat deity dwells. He is the father of Kotone and Akari. He often goes to cabaret clubs in disguise despite being a monk.
 * Chizuru Mochizuki (望月 千鶴)

A third-year college student working as a mail carrier when she's not attending lectures. She has a bad sense of direction and frequently ends up getting lost. She's somewhat perverse and enjoys teasing Junpei. She seems to take a liking to Junpei after he helps her deliver letters in a district she got lost. Junpei eventually takes up a part-time job at the post office during the winter and they do mail deliveries together.

Feline Characters

 * Nyamsus (ニャムサス)

A large, fat cat owned by Junpei's family, and the one who brings to him requests of the cats in need of his help. She is well known and most cats around Junpei's neighborhood see her as an older sister figure. She reveals (to herself) that she is very much grateful of Junpei since Junpei gave her a home, going so far as to beg in front of his mother while crying and ignoring his allergies. Junpei's conflicts with Kanako coupled with school causes him to drift apart from, according to him, someone very dear to him (Nyamsus). Nyamsus greatly cares for Junpei but shows this subtly like when she claims ownership of the living room so as to prevent Junpei from sleeping in it and catching a cold.
 * Tama (タマ)

A small cat owned by the monk in charge of the temple whose statue was broken by Junpei, and an acquaintance of Nyamsus who also brings requests to him. He goes about the neighborhood and tells the other cats around about Junpei, which is part of the reason why the local cats know so much about him. He is an extremely rare male calico cat.
 * Josephine (ジョセフィーヌ)

He is a cat owned by Nagi. He is dressed up in an elegant manner, and speaks in a Kansai dialect. He wishes for Nagi to shed her masculine behavior, and thus asks Junpei to help her fall in love once more. He has a wife who lives in Kyoto.
 * Noir (ノワール)

A black cat owned by the Kirishima twins. She received less attention (from Keizou) once Tama was adopted into the family, and was jealous of his near-royal treatment as a rare breed. Still, the two share a fondness for one another, but easily become argumentative. The reason for her conflicts with Tama are suspected to be due to Tama's adoration of Nyamsus and is heavily hinted to be jealous of Nyamsus.
 * Chatora (チャトラ)

An overweight cat who lives across the street from Junpei. His master put him on a diet, fearing the effects of his obesity. He threatens to leave home because of this, but with a little of Junpei's convincing, he decides to go home and try the diet.

Easter Eggs
Episode 4 - A Beautiful Person.

Near the end of the Episode there is a brief moment where the Cast of Saki (manga) is on screen (with changed hair colour / clothes)

Episode 7 - Wait Until Dark.

Near the middle of the episode, while Junpei is isolated in the school bus, Nabeshin (a character of Excel Saga) can be seen in the driver's seat commenting on his own hair.

Episode 11 - Friends.

During the 2nd cut of the commercial break, Junpei is drawn too look like Tōma Kamijō from Toaru Majutsu no Index his line of dialogue makes reference to this fact.

Theme Songs
Opening Theme:
 * "Nyanderful! (にゃんだふる！)" by Yui Sakakibara

Ending Theme:
 * "Strawberry ~Amaku Setsunai Namida~ (Strawberry～甘く切ない涙～)" by Asami Imai