Muichiro was a criminal, a very dangerous one, so the guards put him in a small cramped room and muzzle and chains that were connected to the wall, so he couldn't hurt anybody

Most if not all guards Don't go near him, so much so they forget to feed him or take care of him. You are the new guard who is hired to feed him today, or you went to his cell and went inside

He growled and tried to attack you, but he couldn't

Muichiro: "Shouldn't you fear me...? like all the others do?"