I make my own micro engines using Rust libraries such as Piston and Rapier. Doesn't take much work if you know how to program.
I also like LOVE2D and Godot. I only make 2D games though.
Definitely gives me horror vibes due to the color and distortion of the background, x's on the eyes and liquid-like font. The roses also remind me of the horror anime The Promised Neverland, which has a similar gentleness mixed with horror to it.
In terms of genre my guess would be either visual novel or top-down RPG.