Quite literally a masterpiece. I could write a long-winded review covering all aspects of the game, but it's honestly pointless. Do you like monster sex? If the answer is yes, then this game is a must-play. Plain and simple. Every genre has a couple of games that everyone should play at least once, and this is one of those. But here's a quick rundown of what you can expect:
First of all, you're not playing this game for the story. There's a little bit of plot here, but the plot is a tool that serves the porn, not the other way around. And that's fine. It's great, actually, because this game has a lot of content. Tali gets fucked in every position imaginable and then she gets fucked some more. What's amazing is that even with how much porn this game has, it never feels like a glorified gallery viewer. The scenes actually make sense, and it's especially fun to see Tali's different reactions based on her "Lewd" level.
Speaking of which, yes, corruption is a major element here and you have a lot of freedom to play around with it. You can lower and increase Tali's corruption level at will, which gives you reason to revisit the same scenes without things getting repetitive. I recommend that you play with URM installed, as you can quicksave and change Tali's lewd level in the middle of a scene to get different results. Sometimes it's just a different line of dialogue, but most of the time you get an extended scene, different positions, a more proactive Tali, etc.
But just to be clear, the main appeal of this game is non-con monster hanky panky. If you prefer a more "organic" approach to corruption, you won't find it here. The ship is full of horny monsters of all species, shapes and sizes. In fact, that's where this game shines. You can tell that the author actually likes what he's creating, because the amount of variety and creativity with the monsters is honestly astounding. It's a game that goes all the way with its main theme, no-holds-barred. Animal mutants are the focus, but the game also has humanoids, xenos, alien insects and optional futa. A lot of it will feel familiar if you've played Mass Effect, but prior knowledge isn't necessary at all. Anyone can enjoy this game.
And just as a side note, I really appreciate how this game handles its subject matter. Tali gets "corrupted" but she's still the same smart and lovable Tali we know and love. What I mean is that she doesn't lose brain cells throughout the game as she gets fucked by these monsters. Even after everything, she's still embarrassed whenever someone mentions her "activities" with the local wildlife. The decision to preserve her intelligence and sass shows a degree of respect to the character, and I honestly hope that the sequel follows the same vibe. Hell, when Tali finally manages to escape this situation, she could probably go back to her normal life at the Normandy like none of this ever happened. Just her and Shepard having sweaty sex every day (great idea for a low corruption/virgin ending, btw).
And if you're someone who values animations a lot, rejoice, because every sex scene is animated. Don't go in expecting realism, though. The art style is deliberate and Tali's body has to be very malleable to deal with some of these monsters. But seriously, these are some of the best animations I've ever seen in an adult sandbox. It really feels like this game is a labor of love, because you have to be a madman to animate so many sex scenes like it's nothing and still come up with new ideas to keep things fresh.
In conclusion, great game. It's a must-play if you like monster sex. I'm sorry if this review felt rambly, but all you need to know is that this game is a masterpiece. I'm genuinely looking forward to the sequel.