I believe that everyone is talking about two forms of orgasms...both dealing with being anally penetrated. The first is the hands-free orgasm, where the bottom cums without any touching or stroking of his own cock.....he cums simply from being fucked and having a hard cock inside his ass. These orgasms normally happen as the prostrate is being rubbed and stroked---I have experienced many of these......my own cock is usually rock hard and explodes with lots of cum during orgasms. These orgasms are more intense and more powerful than a "normal" orgasm achieved from direct cock contact/stroking/sucking....they seem to generate from "inside your ass" and explode through your balls and cock......just a wonderful experience...
Then there is a true anal, full body orgasm---where again, the bottom is being anally penetrated, but the feelings and pleasure just go to another level--almost a physical, mental and emotional (spiritual?) level. Its more than the physical pleasure of your prostrate being rubbed and stroked....just the feelings and sensations of having another man's cock deep inside your ass....letting go of all inhibitions, relaxing, controlling your breathing, and focusing on the pleasures emanating from inside your ass....the pleasure just takes over and rolls through your body in waves........It has only happened to me once after almost an hour of dildo play.....my body just started shaking...first my legs...then hips.....then upper body......kind of scared me......my cock was semi hard....precum flowing....but I never came.....stayed close to cumming, but just stayed right there at that level......for like 10 minutes.......just crazy, intense pleasure........A different kind of pleasure.....more intense, and just lasts and lasts.........
I've been close to that full-body anal orgasm several more times since that one time...but without going over the edge........It's a beautiful thing once you get there. Hope this helps. Peace.