Tsubasa met a crying man one night on her way back home. The next day, that man turned out to be her new teacher. Tsubasa found out that Amano sensei liked astronomy and she joined his astronomy club. Little by little, Tsubasa fell in love with Amano sensei. The astronomy club and the aeroplane club went on an excursion together (the teachers incharge are good friends). Something exciting happens at the public bath they went to and Amano sensei ended up fainting. While Tsubasa was fanning him she heard him called "Mari" in his dream. She wondered whether Mari was his girlfriend but later on Amano told her that Mari was a dog! When Tsubasa went home (feeling really happy that Amano didn't have any girlfriend), Amano had a flashback about a girl with wavy hair asking him to take care of a stray dog. The girl named the dog after her which is Mari!