It's an open secret that I like Succubi, so naturally I was interested in this game. I have my own issues with it, but I'm reviewing it on the merits of the game itself, not what I like, so here goes.
Succubus Heaven revolves around three exorcists investing a strange miasma, which leads them into a sexual version of Dark Souls. (Ed: I have not played Dark Souls). You're able to freely switch between the three girls, who can each have four things (weapons and items) and their inventory, one of which converts weapons into ranged magic. Whichever character you're not actively controlling will operate on some pretty decent AI. The runs are, by design, short, and every run nets you points which unlocks blessings to make the runs easier, and curses that handicap you in exchange for higher points.
The gameplay here is pretty nice. It's a known issue with H-Games that they can often trade gameplay for sexuality, but this could very easily be played more or less as a normal action RPG if you were careful not to get your clothing broken. There's not a lot of complexity to it, but what's there functions well. The H aspect of it comes in with the grabs and clothing damage. Once your clothing is broken, you'll passively take arousal damage, increasing the more damage has been done to your clothes, and being fully naked opens you up to full rape by the enemies, dealing very high lust damage. Every time the lust bar fills and you orgasm, more of it is filled with corruption, and when a fully corrupted girl goes down, she can't get up by herself. This does an excellent job of discouraging careless playstyles, and the game gives you tools to protect yourself from corruption, while keeping actual ways to reduce it hard to find. The blessings and curses add a lot of replayability to a short gameplay loop, and the recent addition of the arena gives you the ability to refight bosses at higher difficulty, as well as a couple of bonus challenges.
But how is the H-content? Well, that's going to depend on how monsterous you like it. The two succubi that you face exactly twice, and the slime maids, are the most 'human' enemies you'll face. From there it goes from zombies all the way down to actual bugs. If that doesn't squick you out too much, then this game has very passable H scenes. There's nothing groundbreaking here, but there's something to be said for sticking to what works. The biggest challenge you'll probably find is that your NPC allies are a little too eager to come to your rescue, but there's a gallery for actually viewing the H scenes, and other than some wonky camera control it works well.
The recent update added a lot of features to the game that really made it an entirely different experience, all in a good way (unless you hate Futanari or pregnacy), so despite looking like a PS1 game it's actually quite robust, if unoptimized. Especially moving into certain areas, it has a lag/crash issue. The developer has been working hard to correct it, but some issues still remain.
All in all, it's a pretty decent game, the H scenes are good (censored, but there's ways to decensor it), and it's matched by decent gameplay. Aside from my own issues with it, the lag and freezes make it rather frustrating at times. On the subject of frustration: this is not a game you play one-handed if you intend to win. The challenge ramps up pretty quickly past a certain point, and it ends with a punishing boss rush. The H scenes, while good, aren't terribly deep, so even with the gallery there's not a ton of content here.
It's a pretty fun game that strikes a balance between gameplay and eroticism, not without it's bugs, and it's very much not at all normal human sex. If you're okay with outright monster sex and willing to overlook some technical issues, this is a game you can keep in your library and do a run or two every so often.