One day, Natsuo, a part-timer, picked up a young man, Keisuke, in front of his house. He began to look after Keisuke, becoming attracted to him eating so deliciously. They have sex as thanks for the meal. They don't even know each other's names.

It was a strange relationship. But Keisuke suddenly proposes: "Let's learn about each other one step at a time, day by day!?"