Nothing physical will ever come of it. I will never meet the "other woman" in real life (though I trust her discretion), and I don't assume a reciprocal image (though it would be nice). I'm being safely exhibitionist, if that makes sense?
This is part of why I'm here, fantasising online instead of sleeping with other women - it's my way of remaining faithful to the woman I love, no matter that she is the most "vanilla" person I know, who I fell deeply in love with before I discovered that I wasn't vanilla (to the extent that simply mentioning my proclivities to real-world colleagues could cost me my job!). There's a small handful of folk here that I trust enough to call friends, who have helped me learn about my own sexuality without making me feel guilty, who I have helped (a little) to explore their own situation. Finding other people to "play" with is just a bonus.
Sorry, didn't mean to get so deep & meaningful...