The story is about Saiko, a lesbian tutor, who awakens her student Miko to lesbianism. During a girls' talk session during the break, they grow closer, and Saiko begins to seduce Miko, who likes cute girls regardless of gender. Miko, who is straight, becomes excited by Saiko's sudden closeness. Saiko gradually teaches her how to kiss and how to play with her breasts, and Miko climaxes with her first cunnilingus. Miko is still excited from last week's "lesson," so Saiko keeps telling her she'll teach her more. Miko then repeats what she was taught, this time stimulating Saiko. She brings in adult toys and things escalate day by day, making Saiko climax over and over again.