Fantastic game, I loved all aspects of it! The gameplay is smooth and intense, the visual effects for the rain and blood are great, and I love the sound effects. It feels great every time you pull off the parry.
Only thing I can think to suggest is to consider having the first enemy be easier to parry to help teach the mechanic. I think the visual language is perfect and easy to pick up, but I imagine some players might have trouble at first if they're not used to games like this, so a more forgiving window to parry the first enemy could help introduce how parrying is supposed to feel.
Not that the game needs it, I'm just reaching for anything to suggest. Great job!