Akane, the mother of a childhood friend named Tatsuya, is caught bathing by him. Having always treated her like a mother figure since childhood, he tries to gently apologize, but finds himself overwhelmed with arousal. In an attempt to prevent things from spiraling out of control, Akane decides to handle the situation herself, only to further excite Tatsuya. From this moment on, their relationship takes a deeper, more intense turn.