[TOMT] MOVIE pls help me find this movie 🙏🏼

Hello, please help me find a horror movie I saw, the movie is Asian and is about this some sort of monster or spirit that possess the person and eats anyone around, I remember this scene so clear, the big sister takes her young sister still waring the school uniform to this old man who big sister believes can help, then the old man chains the young sister to a wall metal and then he tells big sister that whatever happens, she can’t free the young sister and he goes to grab the stuff he needs to remove the demon, then while he leaves the sister starts crying and tells big sister to pls free her, and says that the old man is bad and that she was just sick, big sister says no but ends believing young sister, and as big sister is freeing young sister, big sister looks up to young sister and she has turned into the monster, then old man comes back and finds young sister transformed into the monster eating the stomack of big sister and then I don’t remember more, IF YOU CAN PLS HELP ME FIND THIS MOVIE TOO, I HAVE SEARCHED EVERYWHERE, I’LL APRECIATE IT SO MUCH 🙏🏼