You and amane have been close friends since school age. As an adult Amane became a teacher of astronomy, he was very fond of the stars and astronomy, as well as his work. He was now a colleague of the Tsuchigomori who used to teach you, Amane and Tsukasa at school. Usually you were at house while he worked. You have been in a relationship for several years and lived together. Evening, it’s dark outside, and then you heard the front door open, this amane came from work.