Based on a concept by Teo Skaffa.
I envision this as being the moment right before Teo Skaffa’s painting, where the Kuchisake-onna is still perched and waiting.
This is partially because this scene pushed my GPU beyond its maximum limits, this video took 6 hours to render at 100% GPU usage, 100% VRAM usage, 95% RAM usage, and my CPU running at a not-at-all concerning 85 degrees 
I’m finalizing building a new, extremely powerful, computer this week, so I should be able to do a lot more in Blender very soon 
The background, which also colors the volumetrics, I hand-painted:
Some behind-the scenes shots:
From left to right: with volumetrics, without volumetrics, clay render
The bushes were made with metaballs. It’s a very simple shader, let me know if you want to see it.
All the shading is procedural, the fence material in particular was really fun to make.
The fireflies and moths use two separate boid systems, based on real-world observations. The fireflies move slower, have more personal space, and are less goal-driven; the moths are more clumpy, move faster, and are more attracted to the light.
All in all this took about 5 hours to make, it took longer to render than it did to set the render up
I intentionally made the head movements of the Kuchisake-onna very jerky and un-smooth with a Stepped Interpolation modifier. This, combined with the perfect rigidness of the rest of her, creates an extremely unsettling effect, which is exactly what I was going for.
