The face.
I’m a huge fan of armpits, forearms, thighs, taints, balls, and assholes. However, since I was a kid, for me the sexiest part of a man is his face. I don’t even need porn. I’m happy to stroke one out looking at a handsome mug.
I was mostly a top my whole life until about 50, when a masseur introduced me to the exquisite pleasure of prostate orgasm. I had a good decade with it until I lost it to cancer. I have now found out that my anus, sphincter, rectum. and everything else “down there” still delivers a huge amount of pleasure. I actually find penetration easier now. Consult with your doctor about how long to wait before attempting penetration.
I have had them since puberty. Lost my prostate to cancer a while back. While I miss the prostate pleasure, there are all sorts of other sensations in receiving anal stimulation that still give me intense joy.