Jockey Pouch Midway (or Boxer) briefs by Jockey.
I swear by these. 96% cotton, 4% lycra. In gray, black or white. You have to go up a size if you have an ass or big thighs (I have both). So, I wear a Large (36"-38") even tough my waist is 33.5" and I technically should be in a Medium (32"-34"). I wore mediums for a while and they all ripped at the seams (my hips measure 42" and my quads are 24" each). I called Jockey and their customer service was amazing. They had me wash them, return them, and they replaced every ripped pair I had for free and even gave me the next larger size. Seven replaces pairs in all IIRC.
The pouch front makes for easy access for urination and play ( I hate the "Y" front of traditional briefs) and the pouch gives you a nice bulge.
Here is a
pic. The bright light washed the pic out a bit, but you get the idea.