At the start of her arc, Mai is already in a relationship with Kamiya Jun, after they were paired by the Coupling Center. Mai is a second-year student and writes romance novels for an established publishing company. The characters in her novels seem to be based on Jun and herself to a degree. She also draws inspiration for her novels from ero-manga and personal experiences.
The cousin and arranged fiance of Sachiko; in order that a trusted man inherit the Ogasawara company, their engagement was arranged, although Sachiko detests it and denies that he is her fiancé. (It is later revealed that Sachiko once loved him and had her feelings spurned, which resulted in her disdain.) First introduced when he is given the role of the prince in Cinderella: the joint play put on by the Hanadera school and Lillian Jogakuen. He has prestige in the Hanadera school since he is president of the Student Council there. However, by the time Sachiko reaches her third year, Suguru has already graduated. He is gay, and has a crush on Yumi's younger brother, Yuuki. He is often seen in the company of Yuuki, taking him along on trips and gatherings, doting on him much in the way that Sachiko dotes on Yumi. He is very arrogant, and is especially disliked by Satou Sei, as both are often at loggerheads whenever they meet, bickering or making snide comments at one another. It appears that they both know of each other's sexuality. Despite his coldness, Suguru does care deeply for Sachiko, going so far as to tell her that when they are married, she can have lovers on the outside since he will only be her husband in name only. Sachiko however finds this offensive, and comes to hate him for it, thinking him selfish. He tries to aggravate his younger cousin so that she will be more open and truthful about her feelings, rather than burying them inside. He has taken a great liking to Yumi and notes that the younger girl has had a very profound effect on his cousin.
Tezuka Kanna loves manga. For that reason, she enrolls in Tokiwa High School's manga artist course. Upon joining, three handsome guys discover her secret-- Kanna's a professional mangaka! How will "God" cope with these "Devils"?
Prim and elegant, Sachiko has a rough side and a very sweet side. She is very protective over Yumi and cares deeply about her. However, Sachiko often has the same problem as Yumi does — she does not share most of her problems with her sœur, causing many misunderstandings. Sachiko is slated to marry her cousin and fiancé Suguru after she graduates. This has caused her some distress since, because although she initially cared deeply for him, he did not reciprocate. They now have a complicated relationship. Sometimes, Yumi must teach Sachiko how to live informally, for example, helping her select her first pair of jeans. Despite her sometimes stern appearance, Sachiko has her own share of insecurities regarding her relationship with Yumi, not to mention emotional insecurities rising from her home life; both her father and grandfather openly have mistresses, unabashedly dividing their time between home and the mistresses, which apparently led to her general disdain for men, as illustrated in the OVA series during a meeting with the student council members of Hanadera, an all-boys highschool. After Sachiko enters her third year, she is now the new Rosa Chinensis. After the arrival of Touko, Sachiko spends more time with her than with Yumi, which makes Yumi jealous. Sachiko goes absent from school which makes Yumi worried. Later, Youko is sent to "bring" Yumi to Sachiko's grandmother house. Yumi finds out that Sachiko's grandmother recently died, which causes Sachiko to go into depression. Sachiko says that she apologizes for the past few weeks, and asks for Yumi's forgiveness; Yumi says that she loves her very much. At the beginning of the summer holidays, Sachiko takes Yumi to her summer home. Whilst there, Sachiko's acquaintances make trouble for them. Yumi intends to leave, but Sachiko refuses. The acquaintances have a party, and invite them. At the party, they ask Yumi to play a musical instrument for Sachiko's great grandmother. Yumi says that she cannot play anything and prefers to sing the song "Maria-sama no Kokoro"; Sachiko accompanies her with a piano performance. The great grandmother is happy because the song brings back memories, and she asks Yumi to visit next year. In the first season, Sachiko is Rosa Chinensis en bouton, her grand soeur was Mizuno Youko, and her petite soeur is Fukuzawa Yumi. In the second season, Sachiko becomes Rosa Chinensis.
The exact opposite of most of the characters in the show: loud, rough-around-the-edges, she loves doing what she can to push other peoples' buttons. She enjoys mercilessly teasing or being mischievous, conducting most of her antics around Fukuzawa Yumi. Despite being a non-conformist in the ranks of the regular girls in Lillian Jogakuen, Sei is one of the wisest and caring characters on the show. Though seeming to have a playful and laid-back attitude, she has experienced many tragedies in her life, especially in her second year. Sei is known for doing things at her own pace, and dislikes being pressured into making decisions and taking action. She took Toudou Shimako as her soeur while in her third year. Her relationship with the first year is seen to one of mutual understanding and selective support. Sei however has an especially close relationship with Yumi. Sei becomes a source of comfort, and emotional outlet and close friend and mentor for Yumi. She is often noticed by others for her unconventional looks; many strangers have assumed that she is a model. Sei is not purely Japanese, and has Anglo features, as seen by her hair and eye colour as well as her Caucasian facial bone structure. After leaving Lillian, Sei studies English and American Literature. Part of this could result from her bibliophile behaviours she picked up during her second year in Lillian when she immersed herself in reading as a form of escapism and trying to understand her conflicting emotions during that time. She drives a yellow Beetle and is a terrible driver.
An immortal companion of Yuta. She was raised by a group of old women that kept her captive and incapacitated in a hut. They were really mermaids that sought to eat Mana once she reached her adolescence to regain their youth. She travels with Yuta since, and possesses a large sense of loyalty and feelings towards him, but due to her somewhat naive and spoiled nature, she doesn't seem to truly realize that her emotions towards him are possibly love or just simple affection.