Can someone explain me what happened to hisashi here http://www.mangago.zone/read-manga...

I would say that he locked himself up in his room, so Shota can't come near him.

I think it was because in the beginning Shouta said that Naruse couldn't be cured and that made Akiyoshi andHisashi unhappy. I think that was it at least.

Thanks for that. Now I feel at ease(づ￣ ³￣)づ