its a Petscop au! (aka a digital horror series THATS PEAKKK)
Runie basically finds a game cartridge (that was not left by his mom) and plays it. After a while the game begins to show parts of his life and his family and he gets creeped out. There is an antagonist in this story, obviously, but I didnt really know how to incorporate it into the story(?) but Runie gets kidnapped and very bad stuff happens to him (Its called the Rebirthing process in the series)
Runie finds his way home eventually I promise! He just needs to stop wandering the Newmaker Plain :>