Fun
Sorry. None.
Aesthetics
Very bad. The lava hasn't been made seamless, the colors have no cooperation, and the coins seem to be from google images.
Music
None.
Sound
None.
Mechanics
You are supposed to collect coins and avoid rocks I think? Except the collisions don't work.
Story
You are Charon?
Theme
Charon is the shepherd of the afterlife... So this works I guess.