hey there,
Hmmm, fully understand where your wife's head is at... it is a tough one really. I think the key with most woman is that we don't "think" we will like it, but once we have actually tried it,,, it is a whole different story. My partner enjoys anal stimulation, and it was a huge leap for me to go from using a toy on him, to using a strap on. What i ended up liking as a result was the sense of power i had when using it..... kinda like role reversal. (weird i know, but that is being honest). we brough the beginners strap on set, and it comes with a very nice soft harness, and two dildos...... I suggest just talking to her and saying hey can we try it, and if your not into it we will leave it at that! just see what happens

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not sure if this has helped you.....