瀬戸 修司

Shuuji is a second year student and is the cousin of Aoi and Tsubame. He is also the step brother of Konomi and the childhood friend of Amane, who is also his ex-girlfriend. He left the family home two years ago because he doesn't get along with his father any more and for a year he has been living with his cousins.

Since he joined Aoi's high school, his only friend has been Kouichi (because he doesn't have a very good reputation), with whom he shares a passion for strategy games. He is also a classmate of Itsuki and Shinobu.

One day, he surprised a Senpai who was heavily and ungraciously seducing his classmate Itsuki and he decided to get her out of there pretending to have asked her for an appointment to see her in private. Playing the games, Itsuki joined Shuuji, smiling and happy, sending the Senpai away. However, Shinobu attended (from afar) the scene and thinked that Itsuki and Shuuji were dating, spreading the rumor in all the school.

Taking advantage of the opportunity to scare the boys, Itsuki asks Shuuji if he agrees to play the game and claim to be her boyfriend, which he does because he sees no problem helping his classmate, thus becoming the most watched and envied man of the high school. At the end of the day, returning home, Aoi picks him up in the living room and orders him to explain everything. Shuuji then tells him that he claims to be his boyfriend to help his classmate and that there is nothing more between them. 

Many things happen, and Shuuji finds himself with Itsuki at his side in front of his little sister Konomi and childhood friend Amane who came to see him. The situation is complicated for the false couple of lovers and the stability of their secret hangs by a thread.

Shuuji wants to be independent as soon as possible. For this, he works part-time at the bar-restaurant of the shopping center, the Comeria.

The relationship that Aoi and Shuuji maintain is similar to a relationship between siblings. They heckle, make derogatory remarks and tease each other all the time. However, Shuuji loves Aoi very much, like his sister, and this love is reciprocal. He is ready to do anything for her if she has problems. 

Shuuji never gets sick, or very rarely.

Shuuji's father died a year ago, and he struggles to recover because the last time he saw him they had quarreled because Shuuji didn't accept and find disrespectful that his father remarried with Nadeshiko less than a year after his mother's death so Shuuji had left the house.

Shuuji greatly respects girls and does not want to rush their first time, even if he is deeply in love with her, he prefers to wait until she is ready.

He doesn't masturbate anymore since he lives with his cousins because he is too afraid to be surprised by either Aoi or Tsubame who enter in his room as if it was theirs. Once, at the beginning of their cohabitation, Aoi entered in his room while he was about to ejaculate. He managed to restrain from relieving himself and, at the same time, hiding the fact that he was masturbating. When Aoi loses one of her panties, she always accuses him having masturbated with but it's completely false since he is too afraid to masturbate even when he is alone./