Kokou na Kanojo to, Kanojo no Heya de Shiteru koto

Known as the "Lone Ice Princess," Kitori is a stunning beauty revered by her classmates. Takumi, on the other hand, is a quiet loner, unnoticed by most. Though their paths never cross in the classroom, after school, in the privacy of Kitori's room, they engage in acts that go beyond mere lovers. With minimal disarray of clothing, their connection is mechanical—devoid of kisses or conversation. This act is Kitori's self-invented "Routine," a means to transform herself from the introverted girl she once was. One day, Kitori finds herself saved from a predicament by Eiji, a second-year senior. Charming, cheerful, and kind to everyone, Eiji embodies the ideal Kitori aspires to become. Determined to reinvent herself and emulate Eiji, Kitori doubles down on her routine with Takumi, taking bold steps toward a new version of herself—

A story of two awkward souls fumbling their way toward youth, bound by a secret connection.

(Source: Kadokawa, translated)