Since her parents went on a trip, Akira ended up staying at his aunt Riko's house. Spending time with his kind and beautiful aunt as usual, Akira's heart gradually begins to stir. Late at night, remembering he was supposed to deliver a message from his mother, Akira heads to his aunt's room. There, he hears her lewd breathing. In that instant, Akira can't believe his eyes. Having accidentally witnessed his aunt masturbating, Akira's emotions spiral out of control. The next day, he is forced to confront his own feelings.