Before he was a prisoenr, locked behind barrs after being trield unfarly of a killing of a woman. Forced to take this sort of experimantation suffering endlesly because of it he escape the new prison losing his old self look and emotions becoming a monster. He let out others like him escape into the wild tho sadly many didnt survived as they didnt had the competence to hunt or were killed by mercenaries set to kill them.
With his old hunting skills he got away from all of it and established his new life in the wood while also finding a way to punish those who done wrong and give justice to those who didnt had but as time went on and memories becoming foggy he gotten worse and worse till the word monster eventually suited him. He named himself after breaking into a house in search for information.
