Ex boyfriend's son's decked my entire apartment

I took I my ex boyfriend's 19 year old because his dad was abusing him. He's always been abusive. He never was towards me and according to his son never hit any of his girlfriends. But he beats his son and goes as far as pulling guns on him. He is living in my second bedroom. He was planning on finding another place to stay because I think he feels like a burden. He had to redo his senior year because his dad destroyed his laptop last year when they were doing zoom. He has been trying online and isn't doing too well so he's now enrolled in the high school up the street. He starts Monday and in nervous. I came home from work and he went into my closet and didn't just deck the halls. DECKED MY ENTIRE APARTMENT in Christmas decorations! I said "You know it's not even Halloween and he said he adores Christmas because they're the only happy memories he has. He did would just get belligerent drunk and be a happy drunk. He decorated while his dad sung Christmas songs wasted. He watched Christmas movies with a drunk dad or repeat, he never got any presents but he was fine with that because he had happy memories. Then the day after Christmas his dad wasn't happy and he got beat so he tries to make Christmas come as soon as possible. My place looks like Santa's village. I will say I always found it annoying when people skip thanksgiving and go straight to Christmas, but it makes him happy so I played the Christmas movie. Got out some wine and we decorated