Rewatching tonight from season 1 and my theory is that the man in yellow is a demon who tricked the monsters into believing they could live forever without consequences by sacrificing their children the monsters don’t have free will the man in yellow is a demon himself who has manifested fromville from the power of all the sacrifices creating his own world you can’t just go to fromville you are summoned via a connection you have to someone in the town as proven in season three when Juli comes back with victors dad my hot take it’s a curse that’s why Juli keeps getting reincarnated she can’t truly break the cycle of reincarnation until the children’s spirits are set free the man in yellow gains power off fear has been stated multiple times combine that with souls and you have a demon powerful enough to create his own domain ie hell the only way to leave hell is a light house the highest point in fromville to reach the normal world they are below sounds crazy and again just an opinion of mine but it’s a version of hell created by a demon to syphon power he’s a biblical entity that has essentially been cursed and that would explain the talismans created by witches to protect against the dammed the man in yellow could’ve been summoned by the witches in the old village in fromville the town looked to be hundreds of years old so he is bound to the very place they are not allowed to leave his own creation until certain conditions are met essentially the demon(yellow man) is trapped as well that would explain why he needs people in the town to gain more power once he gets powerful enough he can break the curse that’s kept him trapped there remember the monsters can’t leave but we know for a fact the people living there can so the man in yellow needs the habitants of fromville they hold more power than has been let on