Summary: Belle Delphine gets fucked by thirsty simps on Hoth while collecting Rubix cubes.
In all seriousness though, it's not a bad game. But let's break it into parts, shall we? (TLDR at the bottom for those lazy to read the whole thing)
Gameplay:
If Nier Automata and Dark Souls had a baby., this would be it. Unfortunately, this baby is dysfunctional, crippled, and ugly, but it works. In terms of the character animation and in-game movement, it's actually pretty smooth. The problem is the ridiculous hitbox, as everything you try to slice up would either clear out entire rooms of enemies or completely miss something two inches from your nose.
On top of that, your bones are glass and skin is paper, and a single volley of shots from those defense turrets and you're dead. Those turrets are everywhere and have a longer range than your average sniper rifle. Furthermore, the game has a literal bonfire/soul system where you have bonfires as checkpoints and you lose ALL points on death, and you have to collect it from the spot where you died. That's already a problem, but there is no map, and the environment is disorienting at best, and vomit-inducing at most. You won't know where you are most of the time, and every step you take into new territory carries the risk of you getting your ass handed to you.
Enemies have very few variations. You have those weird dusty simps following you around, some dogs, and some robots. Bosses come in only one design from what I've seen, and most of them die in one hit and kill you in one hit as well. There is no armor upgrade, no weapon upgrades pr any customization in any way possible. All in all, shallow, passable gameplay that may induce suicide in those of you who lack patience.
Art & Design:
It's good, considering it's a DLSite game. I've seen far worse, and this is not one of those. The models look okay, the background and environmental props are polished and well-made but incredibly uninspired and repetitive. Your eyes won't hurt, but you'll get bored really quickly.
Music/SFX:
Sounds like a Garageband mix of Terminator music and some other shit. Not bad, not good, nothing noteworthy. The girl has the typical moan sounds you'd hear in Fallen Doll and most 3D anime porn games these days.
Porn:
Obviously, the focus of the game. It's good for what it is, but all are pretty vanilla and there isn't any difference between the girl getting fucked by enemies or in her private quarters. The costumes do help make each scene a little more interesting but ultimately, once you install the decensor mod on the first page of this thread, it's a solid, fappable experience.
TLDR; It's a passable game. It doesn't take a lot of grinding to unlock all content, but it can be frustrating at times and downright maddening at others. If you want a quick fap, just instantly lose the moment you start the level so you can decide for yourself if the porn is worth grinding for. I'm still giving it 4 stars because y'know, it's a DLSite game.