Airi Akizuki enjoys beginning her mornings with sexual satisfaction. When her stepfather, Kouzou Akizuki, creeps up on her while she sleeps, she feels truly alive. Fully satisfied, Airi wakes up refreshed, energetic, and prepared to face the day. On a crisp summer day, Kouzou takes his stepdaughter and her friend, Sana Kuranaka, to the cinema. However, the pleasantness of the outing is threatened when both Kouzou and Sana fall asleep, leaving Airi alone in the dark theater. She is assaulted by one of her school teachers but must do her best to remain quiet and suppress her pleasure to avoid waking her stepfather. The attacker leaves his victim drenched in sweat and moaning with satisfaction, promising to return soon. To Airi's horror, she finds herself anticipating their next encounter.