Over one year in and there's still almost no sexual content.
This happens often with realtime 3D games. The thing is, it's not really hard to make a game with nudity in 3D these days, either using Unreal or Unity.
The hard part comes when you have to make and bake animations and also adapt the standard 3D characters to include vaginas etc, and make them morphable. This requires a bit more than an amateur developer who knows half of what he's doing.
I'm still in the contemplating/planning phase for a project myself and the big hurdle is really to make good looking characters with resizable tits and morphable (animatable) vaginas and assholes, boob jiggling physics and good looking hair.
If someone was to make a repository of characters including all these things, I'm sure they would make a ton of money on small-time developers doing a hobby project.