Riku Seya, usually referred to by his surname, Seya, is a classmate of Maho's, who meets her when they enter the same junior high school. First introduced in the anime as Maho Nitori's classmate, he is generally a soft spoken and kind person.
As time goes by, Seya comes to admire Maho, and her sometimes bold demeanor. Seya is even tempered, and remains polite with Shuichi, though due to their initial meeting, and not understanding at that time that Shuichi is a transgender teenager, there is always some awkwardness between the two. Later, he is shown to be very loving towards Maho, and very caring towards Shuichi, as seen from the time when he finds out about Nitori Shuichi going to school dressed up in a girl's school uniform, and knowing the kind of pressure Maho and Shuichi are feeling because of that, so his sense of fairness and duty, moves him to try and alleviate the bad social karma that develops. Seya stays loyal to himself, but also loyal to his friends in their time of need.
Seya's Story (Anime)
Seya is first shown to be Maho's classmate in middle school ( Jr. High ), where Maho makes an impression on him, and he begins to take an interest in her family and social situations. Seya also initially takes an interest in Shuichi, whom he believes to have been born a girl, when they first meet. When he learns that Shuichi was assigned male at birth, but has a female gender identity, Seya becomes angry at Maho for hiding this, and stringing him along. But Seya soon reconciles with her, as well as her brother, Shuichi, and eventually starts dating her. As the series progresses, their love for one another deepens, and with a love confession by Maho, they become a official boyfriend and girlfriend couple. As such, they begin to hold hands together out in public, as they walk home from school. Seya even offers to be Maho's bodyguard when she begins to once again attend school, deflecting rumor and innuendo towards Maho, because of Shuichi coming to school dressed as a girl.
He is much more soft spoken to Maho then to others, and is able to show empathy and pick up on her feelings, especially when she is feeling the stress from other people's inability to understand why Shuichi one day dressed up as a girl to attend school. He tries his best to alleviate this injustice and prejudice, and show solidarity with ones who are fair minded and accepting of what happened. One way that Seya does this is by holding the same Maid Café at the school festival that he did the year before, but insists that this year the cafe volunteer workers, instead, to do a gender non-conforming Maid Cafe where the guys dress up in blouses and short skirts and be maids, and the girls dress up in formal attire and be waiters or butlers. The gender-reversed Maid Cafe turns out to be a huge success, and Seya is now looked upon as a efficient organizer and a proper business role model.