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by MadScript (their first game). An Escalayer-like where you have two girls and if one is cut to 0 HP, then she's captured, you get her rape scene for the enemy, and then your remaining girl has to go rescue her solo (and it's game over if you flub the rescue attempt). if you don't rescue her immediately then you get the captured girl's prison rape scenes. Hilariously, it's actually beneficial to let a girl get captured and let her stew for a while. You see,
she gets training exp while captured, and at a much faster rate than she could when free. And if you haven't raised either girls stats yet, you WILL have a girl get captured when you take a crack at the first boss and he one-shots whoever is in the front position. The penalty for leaving a girl captured is that her max MP drops every day (bottoming out at 10) but if you just started, that's barely a penalty. So the mix-max thing to do is let one girl get captured, let the enemy train her for a while, recover her, and then let the other girl get captured and trained.
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by yaminabedaiichikantai - very much has the mechanic (if a girl is cut to 0 HP, she's captured and you have to do a rescue as the other girl) but has one major problem. Which is that the game is dogshit. I remember needing to using MTool's built-in cheat engine stuff to make it bearable to play, and then blasting right through it because it's really simple once you skip the grinding.
I
believe
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by B.H.C. has this mechanic but I'm not positive. The game is a slog to actually play, so I never experimented with the mechanics. But if I understand correctly, if you lose some of the boss fights then you get a special attempted rescue sequence by other magic knights, with special scenes for them fucking up and getting captured too.