Fucking your sub's throat until he passes out. Bringing him to the verge of death. You don't want to kill him, oh no. But you do want to cause some lasting damage.

Kimk event where the main attraction is a public recorded rape.
You can sign up beforehand and you'll be tested and put in the raffle to be used and then put into a crowd.
Security will grab a girl at random and chuck her in stage
Poly relationship that's started with one person raping the other mombers so they get together to confront them but end up helping their rapist use their new partners
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This isn't a fully formed fantasy but I'm thinking of lobotomy kink. Being reduced to a stupor, wetting yourself, being totally compliant and retaining only a sliver of your former self
You're too stupid and naive to realise your new boyfriend is intentionally making sex bad for you. He goes too hard, too fast. He makes sure you're not wet enough. He pressures you into anal and makes it hurt. And into no condoms, making you nervous and unaroused. He loves that you hate it.