One: Kagayaku Kisetsu e

One: Kagayaku Kisetsu e (One ～輝く季節へ～) is a Japanese adult visual novel, developed by Tactics, a brand of the joint company Nexton, and released on May 26, 1998 playable on the PC for Windows 95. Much of the staff that created the game later became the founding members of the visual novel company Key. The game was later ported to the PlayStation, and re-released as a full-voice version for the PC. A sequel loosely based on the original One visual novel entitled One2: Eien no Yakusoku was produced by BaseSon, another brand under Nexton, and was first released in April 2002.

Two original video animation (OVA) series were created loosely based on One. The first, which had the same title as the original game, was an all-ages OVA published by KSS between 2001 and 2002 with four episodes. The second series, by the title of One: True Stories, was adult in nature, and published by Cherry Lips between 2003 and 2004 with three episodes. One: True Stories was later licensed for English language distribution by Media Blasters. Other adaptations include four novels, drama CDs, and manga anthologies.

According to a national ranking of how well bishōjo games sold nationally in Japan, the One full-voice edition for the PC premiered at number twelve out of fifty in the ranking, and ranked the following two weeks at forty. In the month that followed, the One full voice edition ranked first in sixtieth place, and then again in the following ranking at forty-four. The six heroines from One have appeared in the Eternal Fighter Zero dōjin games by Twilight Frontier.

Gameplay
One's gameplay requires little interaction from the player as most of the game is spent on reading the text that appears on the game screen, which represents either dialogue between the various characters, or the inner thoughts of the protagonist. Every so often, the player will come to a "decision point" where he or she is given the chance to choose from options displayed on the screen, typically two to three at a time. The time between these decision points is variable and can occur anywhere from a minute to much longer. During these times, gameplay pauses until a choice is made that furthers the plot in a specific direction, depending on which choice the player makes.

There are six main plot lines that the player will have the chance to experience, one for each of the heroines in the story. Each plot line can be achieved through multiple replays. One of the goals of the original version's gameplay is for the player to enable the viewing of adult scenes depicting Kōhei and one of the six heroines having sexual intercourse.

Setting
One's story takes place from November 30, 1998 through March 30, 1999, although only Akane's route lasts that long. The main part of the story takes place at a Japanese high school, though little is shown except for Kōhei's classroom, the cafeteria, and a little of the surrounding area. The main school building is three-stories, and the roof is accessible, albeit with a sign on the roof's access door saying "No Entry", but the door is never locked regardless. Adjacent to the main building is another which houses club rooms. The school borders a forest on one side with a chain link fence. Beyond the forest is a park with a fountain and a flight of stairs on a hill. Other than the school, the shopping district in town and the usual path Kōhei takes to school are shown, but otherwise the only other place depicted is Kōhei's two-story house.

Main characters
Kōhei Orihara is a young man in high school living a normal life. He tends to tease the girls he knows, especially his childhood friend Mizuka Nagamori, but deep down he is generally nice to girls. Mizuka usually takes good care of him, and worries about Kōhei, wondering if he could suddenly get a girlfriend. She is constantly sighing, being made to go along with Kōhei's meaningless jokes. Kōhei meets a transfer student named Rumi Nanase early in the story whose goal is to become a "true maiden" and to that end, she behaves maidenly toward those around her, but she shows her true character just to Kōhei, who leaves a terrible first impression. Kōhei gets to know a quiet classmate named Akane Satomura who does not readily open her heart up to those around her, and refuses any help Kōhei may offer.

Kōhei also meets a blind upperclassman named Misaki Kawana who has a sociable personality where she can be unreserved with anyone. A mute underclassman girl named Mio Kouzuki meets Kōhei one day and uses a sketchbook to carry on written conversations. She belongs to the drama club, and despite not being able to speak, can still show emotion through various abundant expressions. The last girl Kōhei gets to know is a junior high school student named Mayu Shiina who has a hot temper and refuses to go to school. Her one and only friend she could trust in life, a ferret named Myū, dies shortly before she meets Kōhei and the other main characters.

Story
The story revolves around Kōhei Orihara, the main protagonist, who suspects that at some point his current life will change while living a peaceful daily routine. His parents died when he was very young, and after his younger sister dies, he begins to seclude himself in the Eternal World, a world within his mind. The game's main recurring motif is a focus on the Eternal World, a mystical alternate space which is never clearly explained, and the details of which are unknown. Shun Hikami's remarks in the original game are possible clues about the Eternal World.

The Eternal World is a place similar to the afterlife accessible to anyone, though returning to the real world is difficult. The person's "other self" awaits in that world. If a bond is found in the real world, a person in the Eternal World can be returned after approximately one year. The area is a common territory where anyone in the Eternal World can meet each other. Once inside, it might be necessary to take a girl as a guide by forming a pledge where a grace period can be granted. The guide to the Eternal World's avatar exists in the real world, but one's memories surrounding the pledge become hazy. This world is only accessible once one has lost his or her grounding in the real world, and nothing can prevent someone from going to the Eternal World. A person about to leave to the Eternal World starts to be forgotten approximately one week before going. However, he or she is remembered the moment that person returns. The amount of time before someone forgets differs based on how much someone thinks about the person leaving.

Kōhei is living a normal life in high school with his childhood friend Mizuka Nagamori, and gets to know five other girls throughout the story whom he tries to help with their various personal problems. While Kōhei likes to joke and tease the girls he knows, deep down he is nice to girls and genuinely wants to help them. In the story, Kōhei is able to form intimate relationships with the six main heroines who include: Mizuka Nagamori, Rumi Nanase, Misaki Kawana, Mio Kouzuki, Mayu Shiina, and Akane Satomura. While a given relationship will start out well, before long those around him start to forget him as he begins to retreat further into the Eternal World within his mind. This process continues until even the girl he loves forgets him, at which point he falls into the Eternal World completely, making it seem as if he never existed in the real world. Kōhei's only hope of returning is to form a strong bond in the real world prior to leaving, and being able to follow his guide in the Eternal World back to the real world.

Development
One: Kagayaku Kisetsu e is Tactics' third title, after Moon. and Dōsei. One's production was headed by YET11, who also contributed to the music in the game. Planning was led by Jun Maeda, who worked on the scenario with fellow writer Naoki Hisaya. Art direction was given to Itaru Hinoue who also worked on the computer graphics along with Miracle Mikipon and Shinory. The music was composed primarily by OdiakeS and Shinji Orito.

Release history
One was first released on May 26, 1998 in regular and limited edition versions playable on the PC in CD-ROM format; the limited edition included the game's first original soundtrack. Both the limited and regular editions of the original game contained no voice acting. On April 1, 1999, KID released an all-ages version in regular and limited editions playable on the PlayStation under the title Kagayaku Kisetsu e; the PS version contained full-voice acting. On September 14, 2000, AI System released One: Kagayaku Kisetsu e Memorial Selection, which was essentially the original game, though the price was cheaper at a little less than half the original price. On January 1, 2003, a full voice version of the PC game was released by Nexton. Kōhei was not voiced in any of the versions.

On February 9, 2007, One was released playable on FOMA cell phones via a Java program by NTT DoCoMo. A second mobile release playable on au mobile phones was released on March 1, 2007 by KDDI. A third mobile release, also playable on FOMA cell phones, was released by SoftBank Mobile on July 2, 2007. The last release by Nexton was on June 1, 2007 as a Windows Vista compatible edition for the PC. Only the version for the PlayStation did not contain adult material. The opening video of the original release is still available for download at Tactics' One website.

Books and publications
Four novels based on the series, written by Midori Tateyama, were published by Movic between August 1998 and April 2000. The novels contained erotic material not suitable for children. Each volume focused on one of the main heroines in the story; volumes one through four focused on Mizuka, Akane, Misaki, and Rumi, respectively. A 143-page official fan book, which focused on Moon. and One, was released by the publisher Compass in October 1998. Aspect released a 95-page official fan book for the PlayStation version of One in October 1999.

Compass also released a manga anthology called Tactics Anthology Comic One: Kagayaku Kisetsu e Chapter in May 1999. Movic released a two-volume manga anthology called One: Kagayaku Kisetsu e Comic Anthology between October and December 1999. Ohzora released five volumes of manga anthologies: three in one series, and the last two as stand-alone volumes. The three-volume series is entitled One: Kagayaku Kisetsu e Anthology Comics and were released between May 2002 and February 2003. The first stand-alone volume called One: Kagayaku Kisetsu e Dōjin Selection was released in September 2003, and the second stand-alone volume titled Hidamari One: Kagayaku Kisetsu e was released in January 2004.

Audio CDs
Three drama CDs based on the original game were released by Movic between November 6, 1999 and January 30, 2000. Two drama CDs based on the all-ages OVA series were released by KSS between November 2001 and July 2002. The first original soundtrack for the game was released on December 6, 1998, and a second followed on September 24, 1999 as a piano arrange album. An arrange album came bundled with the full voice PC edition of the game entitled Sea Roars. A soundtrack for the all-ages OVA series entitled One: Kagayaku Kisetsu e Music from the Animation (also known as One: Kagayaku Kisetsu e Vocal Mini album) was released on August 10, 2001 by KSS. An original soundtrack for One: True Stories was released by ChamberRecords/HOBiRECORDS on November 21, 2003.

Anime
One was adapted twice into original video animation (OVA) series. The first was an all-ages OVA entitled One: Kagayaku Kisetsu e produced by KSS; four DVD volumes were released in Japan between August 10, 2001 and May 24, 2002. The all-ages OVA is loosely based on the original One visual novel and is drawn with a different setting. The second series, produced by Cherry Lips, was an adult OVA under the title One: True Stories. Three DVD volumes containing a single episode each were released between November 21, 2003 and May 28, 2004. One: True Stories was later licensed for English distribution by Media Blasters and the three episodes were released in a single volume on August 16, 2005.

Reception
According to a national ranking of how well bishōjo games sold nationally in Japan, the One: Kagayaku Kisetsu e Memorial Selection PC release ranked in on seven separate occasions. The game premiered at number six in the rankings during the first two weeks of September 2000. During the first two weeks of January 2001, the Memorial Selection ranked in at number thirty, and a month later during the first two weeks of February 2001, ranked in at number 38. Memorial Selection ranked in again at forty-one between the end of February and March 2001, and the following two weeks ranked in at thirty-two. Memorial Selection placed on the list again between May 7, 2001 and May 20, 2001, ranking in at forty-seven, and then for a final time during the first two weeks of July 2001, ranking in at thirty-seven. The One full-voice edition for the PC premiered at number twelve out of fifty in the ranking, and ranked the following two weeks at forty. In the month that followed, the One full voice edition ranked first in sixtieth place, and then again in the following ranking at forty-four.

The One: True Stories adult OVA series was reviewed at Mania.com where the reviewer remarked, "One: True Stories is the perfect kind of entry level or couples type of show that focuses just as much on the story and emotions of the characters as the sex, if not more so." The characters were found to be "appealing", and the story is described as a "fantasy but it's a nice fantasy."

Legacy
After the release of One: Kagayaku Kisetsu e, the game's producer YET11 was the only staff member who worked on the game who was later credited for future titles produced by Tactics, such as Tactics' next visual novel Suzu ga Utau Hi in 1999. The rest of the main production staff for One, along with its predecessor Moon., were later credited with the creation of the visual novel Kanon under the brand name Key attached to Visual Art's.

A sequel loosely based on the original One visual novel entitled One2: Eien no Yakusoku (One2 ～永遠の約束～) was produced by the visual novel studio BaseSon, another brand under Nexton. One2 was released first on April 26, 2002, and then again on April 25, 2003 with added voice acting. One2 used the concept of the Eternal World established in One as a major motif as One had done. The Eternal World in One2 is better explained than in One, though the two versions of the world differ to a certain extent due to the scenario writers that worked on One not being credited on the production staff of One2.

Characters from One have appeared in other media not directly based on the One series. The six heroines from One have appeared in the Eternal Fighter Zero dōjin games by Twilight Frontier. Additionally, Rumi Nanase can be seen as a background character in several episodes of the Kanon anime series by Kyoto Animation. Itaru Hinoue, the art director of One, included illustrations from One in her art book White Clover: Itaru Hinoue Art Works released in 2009.