Having had experience of how erogenous a guy's anal area can be, the idea of using a strap-on on a guy, does appeal to me, but then again, I'm straight, so as you say it's hardly surprising.

Sounds to me like there is something of the role reversal, maybe the power issue that makes it a turn on for you. The male genitals can be kinda threatening (especially when they are first encountered) and penetration is a highly invasive experience for a woman. Perhaps this fantasy has its roots in wanting to give a man "a taste of his own medicine", so to speak.

Meh....whatever its roots....enjoy the fantasy!

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