Perhaps the most embarrassing time was many years ago when I was with my wife and we were visiting her mother, a retired RN. My enema desires were a big secret at that time. My wife hated enemas (bad childhood experiences with her mom), so I was reluctant to ever admit to her I actually like having enemas.
One afternoon, my wife got together with a couple of her girlfriends and went to the city to do some shopping, leaving me with her mother. My excuse for not joining them was "I didn't feel like it". About a hour after she left, her mom asked how I was feeling. I told her I was just tired and had no energy. She sat next to me and put her hand on my forehead to see if I was feverish (I wasn't). Then she felt my tummy right below my rib cage and asked if I had any discomfort there. I answered "maybe a little". Next, she wanted to know when I last had a bowel movement (couple days ago). Did I know what an enema was? I said yes, I got small bulb enemas when I was a child. When was the last time you had one (I lied, said it was years ago). Then she popped the question: "I think it might help if you if I gave you an enema". I objected weakly, but gave in because I thought it would be just a small fleet enema and it would probably be over in 5 minutes. She told me to wait and she'd go upstairs to her bedroom and get an enema ready.
She was upstairs for almost 15 minutes. I could hear her walking back and forth between her bedroom and the bathroom, and soon there seemed to be water running in the bathtub. It was quiet for about a minute when she said, "OK, dear, come on up; I think I'm ready". When I got to her bedroom, there was a 5 liter translucent bag hanging from an IV stand next to her bed. Instead of a nozzle, there was a long red tube attached to the hose. The bag was full of hot, soapy water (I immediately recognized the aroma as that of Ivory soap). She announced that since it had been years since my last enema, a high colonic would be what she recommended. "Now let me help you get those clothes off and we'll get started". When she pulled my underpants off, I was completely naked in front of here. She looked down and saw my erection, then looked up, smiled slightly, winked, and said "We'll take care of that later, young man". I was so embarrassed! Within seconds, I was on my elbows and knees, feeling her slip first an index finger, then the colon tube going deeper and deeper into me. Then the warmth of the enema started to fill my bowels, and made my erection even harder, Soon, there was a sticky fluid oozing out of the end of my penis. She saw it said, don't be embarrassed - many men get sexually aroused whenever they get an enema. It seemed like I was on the verge of ejaculating all over her bed while she slid the colon tube in and out of me! It felt like I was being fxxxxx by my wife's mother!
It took about an hour to complete the high colonic. At first, I could only take about a quart and a half before I had to rush to the toilet. When I returned, she had refilled the bag and started all over. During the third fill, she had slipped the colon tube all the way into me. The feeling was amazing! As the enema went in, my tummy got warm and swollen, and there were no cramps; she had taken complete control over my most intimate bodily functions. After the last fill, she had me lie back down on my back and said it was time to "take care of that little problem you had a little while ago!". She coated my penis and her bare index finger with vaseline, slid her finger deep into me, and began milking my prostate while I masturbated. She maintained eye contact and whispered dirty words as she massaged my prostate. It wasn't long before I shot as big a load of sperm as ever three feet into the air. The feeling was intense, but as soon as it was over, I felt so embarrassed and ashamed. She winked again and said not to be ashamed, this would just be "our little secret" between nurse and patient.