Main characters that look sweet and nice but actually have a dark side!

OK so basically there's heroes and villains in this world the main character used to be hero but his teammates betrayed him and even killed 1 of his best friends on the team he's about to die a but a gift from the friend that died activated and he got trapped in someone else's body and turns out that person is a villain and he swears to take revenge and of course he is going to try to kill them and stuff so he's not soft

Even though it was short I quite liked it was well done even for being short and while reading this he looks like the typical I'll help everyone out and we need stick together but I put him here was because he's calm headed even though he's in a killing game kind of thing and he's not really afraid to die and he also has done a crime in his past but I can't go to any more detailed cause that might reveal who the traitor is and he knows who the traitor is

To be honest I don't even remember what happened cause I read this a long time ago but I think I liked it and it was a killing game kind of thing and the main character wasn't freaking out and like screaming even though he knew he was in a life or death situation so that's why put them here

Long story short his mom was crazy killed guys locked him in the basement told him to get rid of them his mom was killed he snook out of the house he turned crazy while he was in the basement and likes killing people of course he hides behind a fake smile and everybody thinks he's nice and innocent

Sister was killed by an accident because of some guy trying to get to a group he swear to kill everybody in that group and get revenge 10/10!

i don't know how to explain it because it's just not my type of thing to read but still it's good

i forgot about it to be honest but if you want a bad ass MC
you're going to have to wait and be patient

kinda hard to explain but really interesting read and I really like the fact that he is smart
and didn't freak out even when he knows he's in a killing game