It's more 3.5, but whatever.
First of all, if you can't stand some extreme fetishes, don't even try this game out. The story is bleak, characters are weird and hardly relatable, graphics are mediocre, as well as gameplay overall.
However, it does present some of the most hardcore and sick fetishes, and this makes the game stand out. I also liked the exploration side of the game, one of my favorites things in RPGM games. Here it is well presented, and some levels are pretty good.
There is a one in particular when you dive deep into the abandoned laboratory, contaminated with a virus that makes you hornier with each level you descend, and you need to fuck to survive, combined with looking for items. I fucking loved it.
Overall, can't recommend for everyone, but I had my share of fun with it.