Well, our story almost fills your request. Some 35 years ago my wife was married for 4 years in a struggling relationship which she was TRYING to hold together, but they would fight and she was running around sometimes with her girlfriends. She 100% did not bang anyone else while married (until me). She had pretty limited experience before me. She was married to her junior high sweetheart at 16 and WAS NOT pregnant. I took her out for a month before I got in her pants. I was obviously bigger, she told me when my cock made is debut, and that was confirmed when I started trying to fuck her, it took a good while to work most of it into her (she could not take the full thing that weekend after multiple session). She is the tightest I ever had, and I had plenty. She never thought size mattered (never had size). Fucking her was actually frustrating and exciting at the same time. She yelped and lunged away, gave me great sounds, thumbs in the abdomen, hands gripping the sheets, eyes rolling back in her head, multiple multiple "My god your just to big", I don't think I will be able to take you", "I think I am tearing" (Had to stop and let her check for bleeding a few times), "I really want to but I don't know if I can", "Can we just take a break", "OK, just stay right there and don't move" (once I got past the head) but in her words she was completely "Cock Drunk" after a weekend of destroying her. On the ride home she said, "I am pretty sure I love your cock, you, the jury is still out, but that dick...........
Initially she was struggling badly with my 6.5 girth, her ex sounding like 4.5 average girth. She was so tight and her pussy was tight al the way up the channel, a lot of girls are tight at the opening then looser inside, she was like fucking a funnel! I thik it got tighter as I went deeper. After we got the girth in, then we had to deal with depth, and I could only get maybe 4 of my 6.5 inches deep. The helmet on my cock was rubbed raw, and we went though a bottle of hand lotion (Only lube we had) trying to make it easier. She was soaked, but so tight we still needed slick lube. I hurt her but she became a pain freak, lol! She loved (Still loves) the hurt good feeling. Although after 35 years I have to use larger toys to hurt her, 10,000 sessions broke her in, LOL!
She cums vaginally, clitoral, like a machine gun, and had no trouble with orgasms with her ex with his very average size was plenty for her. She honestly could probably lived with average for her whole life and been satisfied..........until she had more! My girth did make her squirt (never did that before) which completely freaked her out. She did not know what happened, but my girth rubs her G spot so hard she cums super quick and many times.
It has to be said though that while my size was substantially bigger, I also fuck to get the women off, that's what gets me off. A girl cumming from what I am doing to her just makes me go longer. Tell me you can't take another orgasm, your going to get a few more until you completely tap out. That is just the way I fuck. Her ex fucked to get himself off, there is a difference. 5 to 10 minutes and he blew his load and rolled off her, done. I remember clearly her asking me "Do you cum?", "Is something wrong?" "Why haven't you cum yet?" "Am I doing something wrong". No baby, you just haven't tapped out yet, "Oh my god your going to kill me" YES I AM! "I don't think I can cum again, I am getting really sore", Shouldn't have said that, that just meant a another 5 minutes, LOL! So with really good stamina (She did not know it could last that long), and good skills and determination to leave a mark when I was finished, combined with much greater girth and a exceptionally tight pussy (think pubic bones), we were match made in heaven (or hell) depending on the session!
And yes, she literally went home and tossed her husband out the next week after our first weekend. So for sure a good fuck put the dagger in her relationship! Of coarse she liked me, but as she said, she loves my cock!