Sanae (An Ogawa) is a high school girl preparing to take university entrance exams. She isn't very good at socializing. She wants to hurry up and become an adult, but it isn't going very well. Over summer vacation, Sanae's sister comes home from college in Tokyo, and her parents decide to hire a housekeeper. Yusuke (Hoshi Ishida), is rough around the edges and a little scary. The people close to him find him a mystery. As Sanae gets to know him, she begins to feel they have something in common...