This was years ago so no hard feelings, but at the time we were both each other's first and had been dating for about 2 years. She was around 19/20 at the time and things were going okay. I'll admit I'm not the biggest at a bit under 5'' but she always reassured me that bigger would likely hurt and average was 'underrated'.

One night were about to have sex and I'm on top of her teasing her before pushing all the way inside her and then she moaned "deeper" not knowing I was already all the way in since she was on her back. Of course, I couldn't do that so I did the only thing I could and started fucking her... but after it was over I couldn't help but wonder if she wanted or would enjoy bigger. Well eventually I found my answer. Around that same time, I learned she was cheating with another guy. I was looking through her phone and saw texts from one of her 'friends'. There was some sexting but also talks about their previous hookup(s) along with some dick pics he sent. He was huge, bragged in the text was 7'' and I believe it after seeing the pics.

At the time I was soo jealous and upset, like it's one thing for her to cheat... but with a bigger guy was so much worse. To know this other guy was not only fucking her but fucking her deeper and stretching her out more was crazy. Had questions running through my head like "did he fuck her better, did she cum for him, did she learn she loves bigger or even a size queen now?" It felt like the corrupted her on some level since i was the only dick she had until he fucked her. So many questions and scenarios running through my head, was hard not to picture it as like 'porn-level' sex with your mind assuming the worst (the best for her). I confronted her of course and tried to reconcile, we were together for a few more months after that and eventually ended up breaking up (her choice). I stupidly asked out of anger how they fucked, and she said she was on top which made it a lot worse since that is a position we struggled with. It made it seem like she was really into it to be on top of him doing all the work.

Years later though I'm a bit envious of hung guys, like that must be so fun to give a girl their first experience with a big dick. To know you're bigger than all her exes and even likely future boyfriend's. That must be so hot and even bit of a power trip. Or to even make some of your gfs or exes/hookups/FWBs into somewhat of size queens when they didn't care about size before.