OMG this is awesome. How do I know? because Ive experienced it. It was a few years back. I was locked in chastity until I had my first wet dream (Day 18). This means my balls were so full they were overflowing. Once that happened I was tied up similar to this, an electro plug was shoved up my bum and he gave me a prolonged anal e-stim milking session. The electrical impulses caused my anal sphincter to contract out of my control, pulling the electro butt plug into me with each contraction. He was basically forcing my ass to fuck itself with the electro butt plug. Also known as Ghost Fucking. I had no option but to lay there and take it through my gag. He varied the intensity from gentle purring in my pussy to big pulses which caused strong involuntary contractions so hard and intense it felt like my asshole was raping itself with the plug. When did he stop? A couple of hours later after my ass fucked itself into a strong anal orgasm. I almost cried from the intensity of the orgasm. I was hyperventilating by the end of it. After I came he asked me if I wanted to be unlocked. I hugged him, barely able to stand, naked and locked in chastity and said No. He smiled, hugged me close to him and kissed me with his tongue deep in my mouth. That night we slept together, him spooning me. No fucking. He didnt have to. He had achieved his aim.