Chaos Labyrinth

Waking up in an unfamiliar room, the protagonist finds himself in a space lit only by moonlight streaming through a window. His body aches as if he's been bedridden for a long time, and he can't remember his name or who he is. Stepping outside, he discovers a desolate section of a castle, devoid of people and lights, with only a full moon shining overhead. A sudden chill grips him, followed by the sound of a distant bell echoing in his head. When it fades, a shadowy figure—something fantastical—appears before him. Chaos Labyrinth is an old-school dungeon crawler RPG, a grind-heavy adventure where monsters are actually schoolgirls. Defeating them (and engaging in sexual acts with them) reveals their past. To temporarily restore a girl to normal, you must defeat her multiple times, but this resets your progress, returning you to the start and losing all skills. You can only have one girl normal at a time.