You wake up to find that your girlfriend looks completely different. And she's acting a little... off. She keeps calling herself, "Tomie" and finally you realize that your girlfriend is completely gone, only her body remains. She's being taken over by a strange being, one who wants you to submit your entirety to her. And for some reason... you're falling for the strange girl before you. You want to please her, worship her, do her bidding. But she warns you, if you step out of line bad things are sure to follow.