I would argue that you are also joined to the skull that eats the locks (I know that is not true and you just changing the gravity but it sort of feels that way) It almost has an 'escape the room' vibe to it and it is an interesting cross between a platformer and puzzler (at least that's the way I saw it). It does get quite tricky at times since I want to move "up/down" when I'm on the side walls by but the game still requires me to move left/right. Unless that's intentional for the design you are going for, I would recommend adding an option to change left/right controls to up/down then the player is no the side walls.