This game is not for everyone. Not just because of its flaws, which I'll talk about in a bit, but because of some intentional design choices.
First things first, Corruption is a visual novel where you use potions to corrupt and enslave women in your town. It has simulation elements where you have freedom to go around town, and need to get jobs to raise money you use to make potions, buy stuff on a sex shop and take the girls out on dates.
What I think is not for everyone is how the progression works. Besides a few sections where you need to see story events to progress, furthering the girls' corruption is tied only to the potions you feed them. You have a lot of intereaction options, but they have no bearing in progressing the relationship. The interactions become lewder and lewder the more corrupted the girls get, and seeing that progression and change is the point of these options and of the whole game. This is for people who get off corruption and mind control more than for people who just want porn.
Also, this game is meant to be played slowly. If you simply grind potions and shoot up the girls corruption level in a few encounters, you are missing most of the content described above, and the thing its fans really value (which is why there's such a discrepancy between review scores for this game).
Moreover, in the end of their paths the girls really become crazed sluts, wearing fetishy outfits and garish makeup, and behaving in ways that make it clear that at that point, they exist just to have sex.
Other thing that may bother some is that there isn't much story to be had. You are out to corrupt women and that's it, there isn't an overarching story or villain/conflict, just watching the progression of each women becoming slaves to lust.
If the points I described above are your thing, the game is pretty good, if not, it falls flat on its face.
Now to the actual problems, the most glaring one is the English. Especially noticeable in the beginning (and older content in general), but still a recurring problem to this day, is the dev's poor grasp of the English language, notieceable even to non-native speakers such as myself. Lots of sentences have broken grammar or just don't make sense as English sentences. You can still understand what he's trying to say decently enough most of the time, but doesn't change the fact it sometimes feels like playing a Japanese game with machine translation.
And even without that, the dialogue and characterization are also paper thin, most characters could use some fleshing out. But then again, it's pretty clear the dev is focusing on quantity and variety of content over the quality of each individual girl. To me that is a problem but not a super major one, as I think it succeeds in offering enough the lack of depht doesn't bother all that much.
It also can get a bit grindy in a first playthrough, but once you know which characters getting corrupted open up the more profitable jobs, money stops being a problem and you can manage your time more freely.
Currently (12/2017, version 0.70) only one of the 10 or so "main" characters (as there's a plethora of girls tied to locations you can corrupt that aren't characters with their own corruption meters) can be taken to the end goal of becoming a full-fledged sex slave, with the other girls falling along different levels of corruption and sluttiness. And the enslaved girl doesn't have any interactions/events implemented yet. Still, it is one of the games of this kind with the most content already, and given the dev doesn't leave it unfinished, looks to be absolutely massive when done.
Incest is also a plus and pregnancy to be added to the game. Graphics could use some work however, and very light on story (not necessarily a negative but you'll have to accept that), non-native speaker, it's not utterly broke english but at times can be a little rough, you should get the gist of it however.
