Cool game!
I liked the artstyle, the controls were very good (even though I would have liked to be able to jump just a little or more by holding the jump button, as opposed to always jumping max height - then again that would have made some of the challenges easier). I reached level 8 and then died by accident and rage-quitted. One thing to improve would be to make the game clearer, it is too dark. I know you are going for a spooky aesthetic, but even that shouldn't interfere with being able to clearly see the obstacles, especially in a platformer.
The platform that drops down in the the seventh level is not something that should be in a game with lives. Normally if a player dies and it is not their fault (i.e the game is trial and death), then it should have infinite lives. Otherwise telegraph the challenges/traps/obstacles perfectly to the player, as otherwise it just feels cheap when you kill them.
Also I can't see the connection to the theme.
Overall a very strong entry, good luck!