Is it more satisfying for a dom to discipline a sub with big or small breasts?
I would think that mature adults in this realm of activity would be long past that.
For me it's doesn't matter. Every woman is attractive in her own way. I can enjoy my craft with big, medium, or small breast.
I don't think it matters either. If anything, in choosing a long term partner, I was after smaller rather than larger. Time & gravity take their toll. Overall, it matters very little when compared to other factors.
I don't think it matters either, they're just appetizers before the main course. 😜
Even if the punishment involves the breasts, the size does not matter as a good Dominant will find a way to do it properly.
Also, a good Dominant does not enjoy having to discipline the sub; it is part of the dynamic, but it is not enjoyable.
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