This animation is super rad! Also I have a theory about these characters! Basically, Mariage is some sort of god or godlike figure that is disguised or in a human form while Julianna is maybe some sort of monster like figure. Basically there’s a cult (from the I am not Insane Animation Meme) that maybe wants to sacrifice Mariage for some reason or use him but Julianna saved him. The two then got very close and things were even getting romantic. However, Mariage eventually went back to the cult to maybe protect Julianna and basically left their human form for a god one. Julianna is very upset about this and even resents him a little for this. Idk if this is correct at all but that’s my interpretation! Hope y’a like the theory!
So I am guessing thath the demon girl had to get to the big tower in I'm not insane meme but the boy made a deal whit the plp who tryed to stop them and he became this powerfull being. But thaths just a theory