It depends on the guy and the dynamic between us. The black man who has had the most significant affect on me would sometimes have me worship his cock for hours and when he ejaculated, the only thing going through my head was his cum.
I didn't ever expect to be fucked in the ass by a guy who was not wearing a condom, but he told me from the beginning, he wanted to breed me.
It took 8 months before he fucked me without a condom and his orgasm was powerful and loud as he filled me with cum. It was obvious to him that I was very nervous about him cumming inside m. The next 3 or 4 visits seemed a bit like his victory laps.
After that he seemed to fuck me for a while and then take a break, to rest until he decided it was time for me to suck him again to completion.
About a year after we stopped seeing each other (as I moved away) he sent me a few videos of us that he'd taken. Although I was more relaxed without the fanfare of his orgasm each time he fucked me, I was somewhat naive.
The video showed that he was still cumming inside me (apparently every time) but I had erroneously assumed that because he was silent and I sucked him off a bit later, that there wasn't a pint of semen inside me.
I don't know what was going through my mind when he dumped his seed inside me, but I suspect my mind was empty and blissful.
Apologies if my answer did not provide the insight that you may have wanted. If you want more details, please feel free to dump your seed inside me and I will let you know what the outcome is