with me it does.
i'll tell you and if that doesn't work then i'm going to hurt you. carrying on after i say stop is to my mind sexual assault.
stop means stop and no means no.
well, i think there's a world of difference between someone saying stop leading up to or during an orgasm because of the intense feelings of pleasure and someone saying stop because they're being assaulted or raped. not only in context, but for sure in the WAY in which it is said.
my last girlfriend, at the beginning of our relationship, hadn't had very good sex with any of her previous partners and was very nervous and reserved about really enjoying sex, letting go and losing control. she'd often say "stop" right as she was on the verge of orgasm...and i'd reluctantly acquiesce. but we eventually talked about it and she said it really was just very intense and she, for whatever reason, felt almost embarrassed about climaxing in front of me. so the next time we did it, when she said "stop," i kept going a bit and asked "are you sure?" she looked up at me and this moment kind of passed between us, and she told me to keep going. anytime after that, i'd double check with her any time she told me to stop and more often than not she'd ask me to keep going. eventually, it wasn't an issue anymore...and the only times she'd tell me to stop were if her leg was cramping up or she wanted to resituate a pillow or something, lol. but it really helped us build up the trust and make her more comfortable with letting go and fully enjoying it.
communication is key, both during sex and in the times in between. figure out why she's saying stop...nervous about an intense orgasm? head slamming into the wall behind her? did they change their mind? do they need a break? sometimes, with a couple of girls, it helped them reach their orgasm to stop for a bit, or helped them crest on to it once it started. and of course, to dolfette's point, if it's less of a breathless, moaning, still clawing at your back "stop, that feels too good" and more of an insistent "no, seriously, stop now"....well, discretion would probably prove the better part of valor. but talking it out is always a good idea. each situation and girl is different, after all.