God Killer is A Part Timer! (Autistic Male reader X Devil is A Part-timer)

Y/n L/n was once A Mortal who hundreds of years ago was sent to the Isle when suddenly he became The Most powerful demon ever, A Being who can easily Kill Gods with A Flick of his fingers, and he ruled for hundreds of years until he decides he had enough and wanted to live like A Normal Human for A While, as An average Part timer.