You just want him to be a loli user.

I think it's the book. If Beetlejuice could have taken his body originally it would have made sense to do it sooner. He only just revealed the book.

If it was based on Miasma then he should have an even higher priority since his stench is Sin Archbishop grade.

Puck might be inefficient, but he's totally boss for saying stuff like "I get why you drool over my daughter but go die now"