It was a fun play!
1) I liked the snarky narration courtesy of the demon, both in dialogue and the inventory. Makes the gameplay feel less boring. I'm curious about the MC as well, it really feels like there's a lot to unravel.
2) Plane-shifting looks cool! I appreciate that enemies are visible on both layers, would've been awful to receive damage from something you can't see at all. I also expected bigger changes, visuals-wise, on the shifted plane. Maybe later?
3) The combat was nice and easy, but as a keyboard user I would have liked some remapping, since as of now everything feels kinda cluttered.