So the demo is VERY promising. Animations are serviceable to good and the monster designs are super fun.
Did notice the green enemies near the end and assume their animations aren't done yet. Hit a similar problem to LookImdone when returning from that section where it would load you into the wall and you'd get stuck. I also noticed if you do the dash towards some walls while in the air you'll clip into it and get stuck as well. The only time it happened was in the final area with 3 enemies, I did it to the wall at the very bottom of the area.
That said all said, I'd like to offer a few suggestions if they're feasible.
For starters what if there was an enemy type who blends in with the walls? They could grab you and yank you inside. Would match up with the current position the player gets held in and you'd just need to make or recolor arms for the interaction. Not sure how you'd feel on this since it seems unlikely you'd be able to spank the wall monster back.
Which speaking of not being able to spank back, I think conveyor belts would be a fun addition to the platforming. And if you intend on adding traps to the mix, perhaps having some of them pull you towards spanking machines? That last one is just a personal request.
All and all I'm looking forward to seeing the project grow and will definitely be purchasing a copy once it's out.