I enjoyed this game! The art-style is pretty cute, the music is mysterious and fitting. It took me a bit to realise that - of course - ghosts can move through walls :)
I think you got the mechanic done well and the keys used for it were well chosen.
One thing: Did you forget to set the output rescaling? The game is tiny, I think you forgot to set it to rendering 4x in size.
Good job on submitting, congrats!