I've actually made some undertale stuff in the past. So I have two suggestions here. Player movement is too slow, feels sluggish and can make some of the attacks in the Aso fight impossible to dodge with unlucky spawns (I found that one the hardest by far). And I think with parries the bullets should be a brighter blue to be more visible, and it should disable the bullet after parry, I won the Soro fight in 2 turns by just parrying the same fan over and over again.
Art is wonderful, exactly the kind of style I wanted for my thing. Wish I had the skills to replicate something similar. Love a good tail scene.