In short: very cute artstyle (which I know it's very subjective), inspired concept behind the game both in setting and gameplay, a decent amont of variation, but clunky implementation of the mechanics, poor explanation and some bugs. This is pretty much the pitfall for all of the games of the developer, witCHuus; a shame that there are negatives since the positives are very good.
Expanding on the above points, the preview images will immediately tell you if you'll like the game or not, since it's carried by that artstyle. There is a lot of variation both in character design and poses (you can even see the succubi naked, or make them assume a more human form). To note that there are very cute CGs for when reach lvl 5 for a succubus, and they're unique for each of the 12 characters. There also is a change in expression and a subtle blush if a battle lasts long enough.
The setting is pretty fresh: you are a recently unchained succubus with the power of inescapable allure and the ability to succubi-fy anyone you "defeat" in a sex battle, be them humans demons or angels. This is mainly to justify the rock-papaer-scissors gameplay and the recruitment aspect, but it's cool nonetheless. Added bonus you can repeat the level in which a specific characters appear, and make them fight with the transformed version.
Now the gameplay itself is a bit boring: while it's interesting to see what new designs and powers you may unlock, the whole rock-paper-scissors concept falls apart because of poor balancing: you either come up with a team composition that WILL win regardless of level and stats, or you may recieve in one attack more damage than the combined healthbars of all your squad. It's mainly about the passives: you'll want one to avoid damage, one the reduce cooldowns, one to buff/inflict damage, and a spare. That's... disappointing, considering the complexity that could have been possible with these mechanics.
The music is just there. Not grating, not great, nothing to talk about. This can be said for sound design as a whole.
On the whole it's an enjoyable experience especially if you tend to be a completionist: if you read this review in full you'll definitely find somwthing of worth in the game.