A few years back (around 2015-2017, I think), I ran into a game on Steam that sounded interesting, but not enough for me to spring for the full price. The gameplay shown in the video had a miniature female demon holding a regular size handgun (larger than she was) running around a house and attacking some set of enemies. It was a 3D game with cel-shaded graphics. The impression I got at the time was that it was the sort of game where you're overwhelmed by a large number of weaker enemies to gun down rather than more sophisticated opponents. I didn't think to add it to my Steam wishlist. I want to say the name was two words, something like "Gun Demon". It is not Gun Devil, which is more of a 2D platformer while this one was 3D, running around the floor of the house (probably with some ability to jump to higher levels). It was a 3rd person (I'm not even sure it was over-the-shoulder camera) perspective, and I think there was the ability to move camera around the protagonist with the mouse or right joystick.
I can't swear to it, but I think that it may have been one of those "adult" games with saucy cutscenes in between the action. Again, never got a chance to play it, but that's what my brain is pushing toward.
I'll include more details if they come to me, but that's all I can recall at the moment.