Mirai met Hotaru, who was also a freshman, at the university he entered. The two became best friends when they attended the same lectures, but Hotaru graduated and got a job.
Mirai, on the other hand, has repeatedly stayed in school and spends his days doing nothing.
Mirai is kicked out of his parent's house and moves into Hotaru's apartment, but life with Hotaru, who has grown up before him, is not as cordial as it was when they were students...
He hates Hotaru now. One day, Mirai can no longer accept the "boring" Hotaru, but something changes when a drunken Hotaru kisses him. He tells himself that it's all Hotaru's fault, and he ends up holding him in his arms.