Miko and Hikari attend the same cram school. After class, while studying together as usual, Miko suddenly suggests, "Want to try kissing?" and the two share a kiss. Afterwards, Miko confesses, "I've been masturbating lately thinking about you." To express her feelings, she begins touching her own pussy and attempts finger insertion while learning masturbation from Hikari. Since it's their first time, their sexuality is still inexperienced, but they explore each other's pleasure and gradually deepen their intimacy. To confirm their feelings for one another, they continue to grow closer.