I've played a few vampire survival type games, but I haven't really played many NSFW ones, but I'd like to give some advice anyways (take my words with a pinch of salt)
I think overal it's a great game with a lot of potential. Although I have a few suggestions.
The idle animationfor the player character feels a bit... bland. All the guy does is expand and shrink. On the topic of the PC, his walking animation feels a bit clunky, it's like he's tryna be caught by the girls the way he nonchalantly walks around.
Also there's not a lot of repeatability in playing the game (I know the game is still in development). Obviously there's levels coming out which would add more depth to the gameplay, with different maps and enemies and such, however I feel like with more incenstive to play the game more than one or two runs would be helpful towards the depth of the game. Something like unique endings that require certain steps in order to complete, maybe add a reward to them as well like unlocking a new weapon or H-scene.
The character models for the girls are fine, but when they get hit they sorta do this weird bob backwards, I think investing some time into making an actual model for when the girls get hit would make the game more immersive.
It would be nice to also have an updated UI, for example the health bar showing a value of health rather than being a guessing game with the bar. Also a specific indicator or effect when you're afflicted with inversed controls by the fairy or slowed by the bartender/cow girl.
On another note, a gallery would be nice. Right now, after purchasing the girl's scene from the NSFW shop, there's not really a way to replay it unless you spend more money, and this is weird cause you already bought it once, it just feel like a design flaw to have to buy it again to re-view it. Having a designated area to watch the girl's H-scene would not only make it easier to view all of the girls scenes, but would offer some replayabilityin the form of completion of the gallery.
Overal, like I said, it's got a lot of potential and I look forward to seeing how the game develops in the future.