What you are talking about is the various stages of arousal.
Full blown orgasm CAN occur especially during retention when you are basically stuck in place, focused on retention and not able to do anything about it.
For me, personally, it's not about sex, but my gonads don't always figure that out.
For me, if it's BEFORE I open the valve, I just wait, and focus on what the enema will do FOR me, NOT what it will do TO me!! I usually settle down in a few minutes.
Only ONE time. just about this time of year. I remember it because I was home from college for Christmas. I had to actually remove the nozzle, get out of knee-chest position, and get on my back for a quick session with what was then my most powerful vibrator! After 2 or 3 minutes, I had to remind myself that I had already taken thew 30 mg bisacodyl and fasted since the previous day's breakfast. It was too late to change my mind. I got back into position, re-inserted the nozzle and got on with it!
I had no additional static from the sexual hormones after that!!