Sinner Wilt is an NPC and an enemy in the first BLACKSOULS game that can appear in front of Dorothy’s house after you give candy to Hansel who’s inside the house. To give him candy you mustn’t pick up the breadcrumbs in front of the house otherwise he’ll turn into a demonbeast along with his sister.
(this post is still WIP and is being expanded/updated)
Wilt will appear in front of the house and claim that he’s their brother. He’s a little bit suspicious because he appears to be scared of the Black Trial, and he will even go so far as to give you souls to buy a Match from Elma so he can feed souls to Hansel and Gretel who are running out of them.
If you follow his storyline and do as he says, he will go into the house and they will not recognize him as their sibling, so he will turn into a demonbeast and attack them. If you don’t save them they will die, and if you intervene you will have to put up a fight with him, and he’s not weak.
Regardless if you fight him before he turns into Demonbeast Wilt or not, he’s a strong enemy.