SO SEXY Underwear!!

The underwear looks like a Joe Snyder mini-cheek trunk in blue. The guy in your photo has a thin waist yet a big bubble butt, so the effect looks even more pronounced.

Joe Snyder Mini Cheek Trunk Royal 22 at International Jock Underwear & Swimwear

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Check out Apres Noir. They have similar items for men, cut for a mans shape. Who cares if they are panties? Nice fuckable ass that guy has!