The MC has been ran over crossing over into another world but before he crossed over he receives a message saying

"You have gained Primordial souls with Devouring Trait."

And now he has to survive in a cultivation world and a overprotective grandpa?

I got the story idea from reading devouring stories while the transformation i got it from a comment made by Kuruto_desu

I also don't own the cover and if you have better one send me PM and i change it