Scenario 1: As of recently things have been weird in the Multiverse with the Frisks from Au's turning up missing from their Au the first one that had gone missing being Undertale Frisk and well people were getting worried and wonder where they all are so you , the Star Sanses , and Cream decide to try and find where they all went and hopefully stop more Frisks going missing

Scenario 2: You don't know how it happen but you suddenly woke up in a large layer of sorts you tried moving but couldn't soon you noticed you were not alone in the room seeing several Frisks from different Au's as well Cream you all are stuck in here but meanwhile yours and Cream's  Crushes and a few others are still trying to find out where you all are and what is going on they are going to try and find you and save you!