Hey superfroge,
I'm sorry to have to tell you that your map has been REJECTED. Although we do have multiple Undertale themed maps, none of them are themed after Napstablook. This is why I think that this is a perfectly acceptable and original theme. But, the parkour and build are not very good. I'm very familiar with the character of Napstablook, and this just isn't a great rendition of him. Trust me, I know it's difficult to build ghosts. But, there are just too many issues with its attractiveness due to the simplicity/lack of detailing and poor shaping/dimensionality. The PK was definitely long enough for a medium but it was too easy in my opinion, you should buff the overall difficulty of the jumps on the map. Furthermore, although you did try to make the parkour varied, there was an overabundance of ladder/trapdoor jumps. I hope you take these criticisms into consideration when submitting maps in the future, good luck!