I personally have always assumed that it's quite rare for "something" to come out. I can't speak for other girls (obviously) but I've never faked an orgasm (for abbywinters or in my personal life) and I've never had anything come out of me.
It's all down to how girls are individually, some girls can squirt (I'm assuming that's what we're talking about) and some of us can't. I also know some models on other sites who pee and say that they're squirting though. Nothing wrong with pee, but I personally don't think it's something you can manage at the same time as an orgasm(?), I certainly couldn't.
But yeah, I've made this point recently, women are physiologically different to men in that some women have little to no visible clues that they're aroused and/or orgasming. Which is why I think "mainstream" porn spends so much time focusing on the male orgasm, there's a lot more to see, whereas a girl who doesn't moan or thrash around a lot doesn't really provide as much of a spectacle. Although it's still super fun to watch quiet orgasms (I hope

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