SDAB-221 The third-year, third-class student Seri Saeba is really interested in sex, so she decided to consult a male friend she's known since childhood.

During break time, a girl in the class was talking about having an orgasm with her college boyfriend. The conversation was too stimulating for Mitsuha. 'Orgasm'? Excited Mitsuha masturbated in the bathroom during lunch break. She bumped into her childhood friend Takashi in the hallway. Their houses are close by, and they've been together since kindergarten. Mitsuha mustered up the courage to ask, 'Do you have any plans after school today? Can I come over to your place?'