I liked to watch how her pussy gripped my dick as I stroked it in and out of her pussy. One Saturday morning, the lips didn't do that. My best friend who had a huge cock had seduced her. They never clung to my cock again. I have seen them cling to a large cock afterwards.
My cock in full erection is 7 and 3/4 inches long and 5 and 3/4 inches in girth. The corresponding measurements of the erections of my young black buddy (my lover and my ex's new husband) are only an inch more than that. So the difference in the size of our cocks isn't the cause of my ex's vagina feeling looser on the head and shaft of my cock, as it definitely does, for the one or two minutes following my penetration of her.
I have worked out and confirmed to my satisfaction that the cause of the initial lack of grip of my ex's vagina on my opening thrusts into her is multi-factorial and rooted in the following repeated observations of mine, and perfectly understandable phenomena; viz:
The grip that my ex's vagina exerts on my thrusting cock is very much stronger when I'm fucking her in my buddy's absence at his college classes, track-and-field and swimming training sessions and out-of-state competitions, compared to the grip it exerts when I'm fucking her with him beside us on the bed---provided I'm not going sloppy seconds after him. In the latter scenario my ex's copiously inseminated vagina exerts no appreciable grip at all on my cock-shaft at any stage of intercourse. She orgasms with me only when I---with a huge effort and jealousy-inflamed lust fueled by having just watched my young buddy rampantly fucking her and ejaculating copiously into her---desperately batter her already fucked-open slippery cervix with the head of my cock in a vain and futile attempt to outdo my buddy. At such times I'm only vaguely aware of her milking muscles contracting on the shaft of my ejaculating cock.
My ex admits when I fuck her in the absence of my buddy that, behind her tightly closed eyes, she vividly imagines that it's him that's fucking her. In so doing she totally blocks out every awareness of the fact that it's actually me who has mounted her and it's my cock that is valiantly thrusting in her vagina. Which of course frees her to focus intensely on her memories of his only moderately girthier, but much gristlier and stiffer, erection thrusting in her and her orgasming on it and eagerly milking it as she habitually does effortlessly, repeatedly and way more-strongly than she ever does mine. But notwithstanding that, I make very sure every time that I shoot my load straight into her beautifully sucky fucked-open cervix.
Of course her vivid overwhelming memories of my enviably younger and handsomer buddy's more lithely muscular athletic body and the super-sexy suppleness and vigor of his thrusting action and his way more strongly jerking ejaculating cock compared to mine, persist as powerfully orgasmogenic factors for her too when it's me that's fucking her. It's doubly shaming for me when she shouts my buddy's name when she finally convulses under me.
Cuckold Heaven or what?