I truthfully didn't expect much from this game, but it was much deeper and more interesting than I'd assumed. It's basically a CYOA style game in which you play as a tentacle monster dropped from orbit with no knowledge of your mission. You explore the world, knock up girls, breed another generation of tentacle beast and basically do tentacle monster stuff.
The writing is good, smutty or otherwise, the story is good enough, and there's a decent number of paths, though they naturally bottleneck at a point.
My only complaint is a lack of guidance when you must make choices. I really prefer my CYOAs to have some sort of hint or general guidance when it comes time to make choices. The alternative is found in this game, where each choice feels rather crap-shooty, as you have no idea whether your monster is capable of executing the plan you suggest. I very rarely felt like I had enough information to make good choices.