there have been a few situations that come to mind..... like feeling him cum in me as i was bent over the kitchen counter then telling me to pull my cutoffs back on and leave. or a bf who liked to cum on me then make me go pick up take away food. or realising that i was in a bj only fwb arrangement. or being with a woman who made me know how she had me wrapped around her finger, making me pleasure her when she wanted. that might have been the best since she did it in different ways for longer
it took me a while to get comfortable with it, so it was a slow realisation. but when i did i enjoyed it. i became sluttier and just enjoyed myself more
When I was licking my wife's pussy from behind and by accident (a real accident) I licked her ass. She has never been into it. She groaned so suddenly and deep that I said 'hang on a sec' and went for another kiss on her ass....she loved it and I spent the next couple of minutes fingering her pussy and tickling her ass with my tongue. She exploded in orgasm....and while we never acknowledged it....she now presents her regularly when we are having some fun!