I thought of this today, and wanted to get the opinion of the group. I think that maybe you start out with a certain number of , say sensor nerve endings on the tip of your penis. The older you get, the less sensitive it is, but this is normal, prevents premature ejaculation, etc. I mean who wants to get off with the speed of their first time, every time? Anyway, I think that the nerves there, when stimulated, send a signal to your prostate,eventually building up your arousal to the point that the ejaculatory spasms happen. I think the Aneros tricks your body into thinking you're getting continual, ejaculation building penile stimulation, that feels really good because (I apologize if I'm way way wrong) the thing you feel is actually a continual manual spasm of your prostate. I don't think your prostate actually starts to spasm during normal sex, until just as you are about to cum. Since this feels good, eventually it triggers the ejaculatory reflex, but since your penis is untouched, namely the seminal vesicles, Your body thinks you are still getting penile stimulation, but haven't entered a vagina yet. So no cum comes out, no refractory period, just the ejaculatory spasms (could these be the involuntaries ?) Which cause stronger anal contractions, which pull in the device to stroke the prostate harder, which causes more ejaculatory spasms, etc. I think it is a circle that feels better and better as your arousal and sensitivity increase. Went on too long, but what do you think?