Played this! Here's some things I noticed:
The concept arts on the GDD were super cool! The character design and animations are also super awesome, I love them!
If you dash while you're not moving, the character sprite seems to get stuck in the dashing animation, requiring you to dash again to make the animations work again.
Considering that the window ledges are also platforms, they could use a bit of thickness to drive home a little more that they're platforms. I wasn't expecting them to be since they look thin, so I was surprised. Some of the background elements like the statues are cool!
I saw in the GDD that you guys took a lot of care into making the character control well, and I'd say it translates nicely into the game. Controlling the character feels really nice and precise!
I do feel like some of the level design at times feels really tight and small for the character. The character's collider can also act a bit funky when you land on top of an enemy or a box.
I like the fact that enemies are able to damage eachother! The music for when your sanity starts to run low is also really good. It's just the right amount of creepy and sinister, and the enemy's that spawn because of low sanity have a really cool design and animations as well!
Honestly, I'd say the only thing that I missed was sound feedback for a couple of different things, because other than that, it was a solid experience. Keep making stuff!