As I'm writing this, I'm vibing to the main menu song. Great work on the music!
I really enjoyed the characters, animations, and smooth movements. And the enjoyable music kept me playing through the times when I was stumped by a difficult puzzle.
A really fun thing about the character is that sometimes it felt like the devil was leading the angel somewhere. Or the devil was blocking me from where i wanted to go
"r" for reset was an awesome touch, thank you for including this. I accidentally backed myself into a corner a couple times and this saved me.
I made it through level 18 (sorry i didnt have time to finish it).
The level design was really good. It felt like i was finding my own way to solve some of them and in others I had to find the right trick. Whoever came up with the level that has opposing staircases and the goal in the center is a genius. I felt very clever once i solved that one.
The only constructive feedback is that the "tons of portals" type levels felt less strategic. For me i was mostly pushing the opposing character thru a portal till the level happened to end. And i wasn't really sure how i did it. My recommendation is that a fewer number of portals or a visual indication of where they lead (pairs of colors?) could help the player understand the puzzle before they solve it. But its also possible that a smarter puzzle solver than me would have understood it more.