I wanna hear everyone's head-cannons/theories.

As title say, since there's not much to go on from main story (since we only meet 3 out of 7 devil kings and some devils), I want to hear everyone's head-cannons or theories about the devils/angels.

Even wanna hear some MC/Minhyeok head-cannons or theories.

For me, my head-cannon would be:

After mc had dissappear, Minhyeok started to collect every single one of pictures he had with them, making most beautiful album, as he wanting to give it to mc once they return to human world.

Let's get this subreddit alive.