First of all, well done! Creative interpretation of the theme and it has a really nice look to it. But I have to admit it got a little tedious after figuring out that it's just the same attacks again and again. I think adding a variation of the non-boss enemies would be beneficial, but they would need to be visibly different. Like different size, or different type of weapon, so you would be able to anticipate the different attack pattern. Else it was just: let him come, block, hit, hit, hit, enemy dies, move a bit forward, let him come, block, hit, hit, hit, enemy dies, move a bit etc. Having several ones coming at once made it definitely more challenging, but it also felt a little unfair as it seemed quite random with overlapping attacks and holding the block throughout felt like cheesing it. Also it seems like the player always pushed the enemy forward during attacks, so you would eventually end up with multiple enemies stacked, especially in the last boss fight, suddenly I had 3 minions and the boss fighting against me... Sometimes I used the kick, then blocked and made a normal attack, but instead another kick was made.
Despite that long list of notes, I still had a good time. The background art was really well done, and I liked that you used modular enemies, that kept it like you were actually going after different souls.