Before launching set your locale to Japanese!Guide (Windows 10)
The game revolves around the Heroines being caught and tortured/losing their strength/power drained. Basically, Magical Girls have a core that’s the source of their power. Their magic power can be drained via sex, and if all their magic is drained their core is exposed to corruption. If their core is totally corrupted, they lose their powers forever and become normal girls. So if you like the idea of “power loss” you might like the themes in the game. Unlike other corruption/mind break games, the girls pretty much never “grow to like it”. Though they may be forced to orgasm, they don’t become ahegoaing whores.