Characters
Rin Kokonoe (九重 りん, Kokonoe Rin)
Voiced by: Eri Kitamura
Rin is a young girl in third grade who has an intense crush on her teacher Daisuke. She has a mischievous nature and proclaims herself to be Daisuke's girlfriend. She goes to great lengths to make him fall in love with her, crossing moral and legal boundaries many times. Some of these tactics include taking advantage of Daisuke's inability to respond to her forcible advances by threatening to scream that he is trying to molest her, even though she initiated them. Despite Rin's mischievous nature she has shown herself to care deeply for her friends and family, going to any length to defend them. Much of her bad behavior is a result of trying to hide the traces of the vulnerable little girl she used to be as a result of a tragedy in her past. Rin ages throughout the story, but worries that Daisuke won't ever see her as an adult.
Kuro Kagami (鏡 黒, Kagami Kuro)
Voiced by: Kei Shindō
Kuro Kagami is one of Rin's closest friends, and frequent "partner in crime" due to their similar levels of sexual knowledge. She is openly contemptuous of Aoki due to his inability to consistently enforce discipline in the classroom, and her belief that he is a lolicon. She is also aware that he is a rival for Rin's affection which infuriates her more as she has a crush on Rin. Kuro has a kinder side to her though as she manages to befriend both Rin and Mimi and is very protective of them. The apparent wealth of the Kagami family allows her to indulge her obsession with following the latest fashion trends. Kuro often wears clothing in the Gothic Lolita style, sometimes combined with nekomimi ears and tail. Kuro's overall distrust of men stems from her mother's divorce from her cheating husband.
Mimi Usa (宇佐 美々, Usa Mimi)
Voiced by: Mai Kadowaki
A quiet, bespectacled young girl whose knowledge of adult and sexual matters is inversely proportional to her level of physical development. Mimi Usa struggles to establish a sense of self-identity as most of her characteristics emphasize qualities about herself which she is uncomfortable with. She is emotionally fragile, and increasingly depressed due to her abilities that her friends don't seem to possess, such as being well-endowed among others. Mimi is also a shy person, but opens up over time from her friendship with Rin and Kuro. She eventually develops a secret crush on Rin's cousin Reiji as he recognizes much of who he once was in her. Reiji tells her to never lose hope that she would one day find someone who would understand and love her, and also encourages her to not succumb to anger and hatred at the world like he did.
Daisuke Aoki (青木 大介, Aoki Daisuke)
Voiced by: Junji Majima
Daisuke Aoki, is a freshly graduated 23-year-old elementary school instructor who has been placed in charge of the third grade class 3-1. Many of the idealistic notions he holds about his job, however, are quickly put to the test as he finds himself dealing with unexpected, complex situations, not the least of which is having a shamelessly flirtatious nine-year-old doing everything in her power to win his affections. Aoki's complete lack of previous teaching experience sometimes makes it hard for him to control his class or maintain their interest, a situation further complicated by the ease with which he is flustered by Rin's sexual innuendo and Kuro's remarks about his status as a virgin. His relatively normal, uneventful childhood also complicates his efforts to quickly and easily grasp the hardships faced by some of his students, though this has in no way discouraged him from trying or diminished his desire to help them. In fact, his seemingly unshakable enthusiasm, hands-on attitude, and emotional attachment to his students has often caused him to butt heads with the more traditional Sae Shirai. Almost from the beginning, Aoki has shared a special bond with Rin, one which has deepened and become so complex over time that even he, at one point, was terrified of Rin and began to fear her, and at another point, he began to ponder his feelings toward Rin, mainly to see her as only a "child". Regardless of the nature of his love for Rin, his protectiveness of her has led him to become increasingly suspicious and mistrustful of the motives of her guardian and cousin, Reiji Kokonoe.
Kyōko Hōin (宝院 京子, Hōin Kyōko)
Voiced by: Ryōko Tanaka
A young, well-endowed teacher who is Aoki's colleague and friend at work. She tries to care for Aoki as he is still new to the job, and also has a crush on him. She has asked him out on several occasions, only to be interrupted every time by some incident, usually involving Rin. Due to her busty physique, she is nicknamed "Boin" (a pun on her name "Hoin").
Reiji Kokonoe (九重 レイジ, Kokonoe Reiji)
Voiced by: Tomokazu Sugita
Rin's first cousin once removed, and guardian. He and Rin share a very close relationship, almost like a father and daughter or a brother and sister. For a short period of time, he was in love with Rin's mother, his own cousin Aki, before she died. After her death he became Rin's official guardian. He is very protective of Rin and does not seem to like Aoki at all because of Rin's affection towards him, which makes Reiji very jealous.
Aki Kokonoe (九重 秋, Kokonoe Aki)
Voiced by: Yuri Amano
Rin's mother, who died of lung cancer when Rin was very young. She revealed to Reiji that the father of Rin wanted Aki to have an abortion, but she refused to do it. She falls in love with Reiji and develops a relationship with him. She soon developed a cough, and was diagnosed with lung cancer which threatened her life, and for the sake of Rin and Reiji, she kept her disease hidden until it was too late to cure it. She entrusted him with the care of Rin after she died.
