As a youngster, I hated enemas. They were a ritual in our household, but both mom and dad did not in any way "treat their patients gently", if you know what I mean. They did not even give us a rinse enema after a soaps enema, making the after effects long-lasting and very uncomfortable.
However, my sister, a couple years older than me, took some nursing courses at our local hospital in order to get a part-time job while we were both in hs in the 1960s, and she learned how to administer as part of her courses. She showed me her textbook and point blank ask (my sister was never shy about asking personal questions) if I wanted to be her first patient. She said her teaching nurse said enemas, while not always pleasant, should not be like a torture session. I said sure, but I also said she had to receive one from me, which surprisingly she agreed to.
I got undressed while she prepared the enema, I laid on the bed (everything was set in a hospital-type atmosphere, just as she had learned). She hung the bag from the bedpost, lubed me quite thoroughly (don't know if this was by the book, but it felt good), inserted the nozzle and opened the clip ... first the first time, an enema actually felt good, not uncomfortable.
When the bag was empty, she said I should lay there for a few minutes, then she said for me to expell. It was not a bad experience.
As I was finishing expelling, she came into the bathroom, wearing a bathroom, carrying the bag which she filled and we walked back to the bedroom.
She hung the bag in the same position, took off her robe ... I had anticipated she was have kept her blouse and/or bra on, but she was naked, just as I had been and still was ... laid on the bed on her back, then rolled on her stomach, allowing me to lube her just the way she had done to me. When I inserted the nozzle, she rolled on her side and I opened the clamp ... the enema flowed easily.
When she had taken the whole bag, she laid there for a few minutes, then went into the bathroom, carrying the bag with the nozzle still in her, told me not to rush getting dresssed because our folks were not due home for another couple hours.
While she expelled, I washed my from the lube and we talked about the experience, which in my mind was as pleasureable as an enema had ever been for me.
She asked if I wanted a second one because she said she did ... so we did a second one and also a third enema each before we finally cleaned up the equipment, got dressed in plenty of time before our folks came home.
While she began preparing dinner (her usual task, she loved to cook, too), we talked about the session and agreed that I would let her "practice" on me if she would "accepted an enema(s) in return." Through the course of the next year or so, we had many enema sessions, both she and I enjoyed them immensly. She also learned to give a very good massage.
During high school and her four years at the community college, she worked in the pediatrics ward at our local hospital, and eventually became a registered nurse and worked her way up to head nurse in the pediatrics department.