Kotori is a beautiful girl called the "Solitary Ice Princess," respected by everyone in class, while Takumi is a gloomy loner. The two, who never interact in the classroom, engage in acts more intimate than lovers inside Kotori’s room after school. They mess up their clothes only as much as necessary and connect physically in a business-like manner, with no kisses and no conversation. This act is a "routine" that Kotori created to change the gloomy version of herself.