Since my last entry, I've practiced about three times. The last time I got my leg to shake a bit, like a dog being scratched in just the right place. This time, I took it to a whole new level. I had today off from work, and I had just come home horny from the gym. As usual, I was wearing my jockstrap and cup. My ass was ready to work, so I slipped in the Aneros and I laid down on my right side, knees bent. To heighten my arousal, I had a long loop of erotic pictures on a screen next to the bed. For the first hour, I was trying hard to maintain that partial contraction, experiencing lots of involuntary anal pumping.
Finally, I straightened my legs a bit and lightly flexed my glutes to add pressure to the P-tab on my perineum. At the same time, I was doing valley breathing into my stomach. I got a little bit of leg shaking, then I rested.
About 5 minutes later, I continued the partial contraction, a bit tighter this time. Again, I straightened my legs, squeezing my butt closed over the Aneros. As I beared down into my stomach and tugged my left nipple, I began spasming all over, thrusting uncontrollably like a jackhammer.
This freaked me out but it felt great. The spasming lasted about 10 seconds, but it could have been longer. I also realized after the spasming stopped that my butthole was still pumping by itself and I'd thrown a strong boner.
I rested again for a while, then started the same technique. I began shaking and thrusting wildly again, my erection began poking outside the side of my jockstrap. Unfortunately, the friction from thrusting began stimulating my cock, and I instantly ejaculated onto my stomach. I think maybe this experience was the fabled super orgasm, at least before I unloaded. What a rush! My heart rate was up for at least 10 minutes afterward.