She is not under the charge of the protagonist. She is often mentioned in staff meetings as a problem child who does not go to school very often. The protagonist happened to see her downtown being relentlessly hit on, and helped her. Since then, he has repeatedly tried persuading her to go to school to no avail. However, she seems to have begun to take an interest in the protagonist. She is also open about her sexuality, and often seduces him by saying things like, “If you do naughty things with me, I'll go to school~". [From Getchu]