Bully was in the army with MC. Bully's victim as a ghost went to him to kill him. Bully kill himself on this night when MC was on guard with him. Later, Bully ghost possess a schoolboy to take revenge on MC. MC exorcism him.
And just now, they discovered that this schoolboy was the brother of the Bully's victim. You know when MC said it was weird that his room was in a mess meaning that it was possessed for a long time ? But it didn't match with how long Bully's ghost appeared ?
Now knowing that schoolboy was the brother of Bully's victim, he connected the dot and discovered that the brother was also possessed by his dead brother for a long period of time. This guy really have shitty luck to be possessed by two ghost. ^^'
Alright I'm confused, someone explain the whole student, army, suicide, brother possession like I'm 2.