>>536026023
I'll give you an unique one.
RJ01093428

The visual and erotic aspect is really low, however if you like gameplay where you minmax number the game is pretty interesting.
See pic, you should get an idea what you can expect from that.
Also another negative point is that the English version is badly translated so you might need to grope around the dark to learn how the game works. It shouldn't be a problem though if you like this kind of stuff.