Never really told anyone this, but when I was at leeds uni (around 2012) I used to flirt with my mates girl (polly) all the time. Nothing ever happened and I thought nothing of it, it kinda turned into a joke between us.

Worst thing is, I bumped into her again around 2018-19 and we started chatting, got to know each other and the flirting started up again. Then one afternoon, I ended up in her flat for a coffee while he was at work. We fucked. Worst thing is, it happened again 2 weeks later. I still can't believe it happened. As far as I know, she'd only ever been with him - they'd been dating for like 10 years or something. She was incredibly cute and looked like a good girl - she turned out to be a bit of a slut in the bedroom.

I've not told anyone about it, but it admittedly turns me on quite a bit. I chat to him quite often and he doesn't know!