The girl who is occupied by the devil has been suppressing the devil in her body. Once she was robbed by a burglar, her relatives were in crisis, which made her power lose control and led to the death of her biological parents.
Jue Wake, who was almost completely dominated by the devil, regained his sanity at the call of his sister. Now he and his sister live a life of revenge by hunting other demons while escaping.
The above is what I think, in fact, the devil killed his parents from the very b