helppp

It's bl. So we start off with a break up scene. One of the guys initiated it and the other guy was pretty nonchalant about about the whole thing. From what I remember the guy that initiated it was pretty hurt by it. The nonchalant guy went by his day and the next thing he knows, there's a younger version of ex at his home. And I think as days went by he kept getting younger?

It had time travel in it and was full of angst. I might remember some stuff wrong.
Pls help