The artwork is very nice for the cat and the backgrounds, the demons are appropriately otherworldly. The music and sounds are nice, though there aren't many.
The wall jumps work very well and are easy to do, in contrast the regular jumps are a little too 'real' with no control once you've launched into the air. It's not too much of a problem in the first level, but the bottomless pits in the second level were too much for me to get through. This is further impacted by the right side of the screen being cut off prematurely, which was evident when I saw I had finished "the tutoria"
The inclusion of boss battles is a nice addition, though I could only experience the first one. It wasn't until then that I found out there was an attack button. :)