Chapter 5.5
One day, Natsuo a part-timer picked up a young man, Keisuke in front of his house. He began to look after the man since 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 each day!?"
Chapter 1
One rainy day, the serious Professor Amamiya comes home and finds a young man named Naruse seeking shelter from the downpour by standing beneath Amamiya's roof. Naruse looks so much like Amamiya's past love that on a whim, the professor invites the young man inside to dry off. Afterwards, Amamiya refuses the young man's contact information out of politeness, but a month later, Naruse reappears. This time, he asks to spend the night...