The graphics are great! I love handpainted textures like that. The dialog system is cool too, and definitely make the game feel more complete. My favorite part was the graveyard level because it looks awesome.
Unfortunately it was very hard to play due to the bugginess and performance issues (tested on a PSP Go). I used the updated build you posted on the comments, and the final boss took forever because that scene ran at very low frame rates, and I think the collision detection had issues because I kept getting thrown back even though I dodged the skulls.
Luckily there was a glitch (feature?!) that made that part easy. You can just press left on the dpad and your character will go off screen, bypassing the skulls completely. Beating the boss seems to soft lock the PSP, meaning the only way to close it is to reboot.
But besides that, nice entry! If you fix the bugs, you'll have a nice little PSP adventure :)