MILF Alexis Golden in one of the Men In Pain videos, dunno if your into that but it was an alright scene, mainly the last 20mins or whatever when the fucking started it got amazing. I gotta say it was prolly the hardest riding i've seen, she was in cowgirl but on her feet (squatting down vigorously) at the end of the scene with the interviews, the interviewer chick said "he was getting eaten alive." Not just a short 30secs of riding either, it's all her on top for the rest of the scene until he cums, ha. Also note: the guy was restrained, but also not over-exagerating (as you expect from those sites) just genuinely enjoying it, but certainly overwhelmed. Oh, it was on a bed too so you can see him slamming down, it's great.
There's also Jill Kelly, a creampie scene, same 'squatting' position as above riding constantly as he cums, although not vigorous... Certainly constant and deep penetration, best creampie scene i've seen, any other 'on top creampie scenes' (underrated) usually finish with the girl slowing down as she feels the cum or the guy stops her, etc.
Well, there's two, I think looking around for scenes with that 'squatting' position is your best bet.
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