The more literal usage of the word "douche" refers to something clean and good (a vaginal cleaner). Yet to be called a douche is much more negative. Also can be used as a negative term in other forms, much more common as negative slang than the literal meaning. Similar to the way that a "fuck" is a good thing, but it's never good to be called one ("hey why'd you do that you stupid fuck!?") or to be fucked over, etc.
To put it in perspective:
In the more literal sense of the word:
When I was younger my priest douched me to clean out my evil spirits.
In the slangier, negative sense:
Now that I'm older and undergoing therapy I realize my priest really douched me over!
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When you splooge on a chicks face, then punch her in the fuckin nose so it bleeds.
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jimbo rammed his fleshy man tube into jane's hairy asshole
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poopsex. plain and simple, yo.
"i want some poopsex"
"be polite; call it turd fucking"
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The area between your ass and pussy/penis
dude, lets hit golfballs off my goosh.
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The unexpected squeezing and twisting of the nipple on a friend. Results in your nipple (nurple) turning purple.
Nathan decided to give his pappy a purple nurple. But pappy was too fast and now, Nathan has a purple nurple.
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In femdom, when a man is made to wear a strapon backwords so that it comes out from his backside so a woman can fuck his body without him getting any pleasure.
'Alice, do I have to be your man doll again tonight?!'
'Don't piss me off, I'm an icer'
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