When I was growing up, it was possible for teenaged girls (high-school-aged) to participate in apprenticeship-type training programs with local practicing doctors/hospitals and dentists. This was for girls who were interested in exploring careers as nurses and dental assistants/hygienists.
My pediatrician and his wife (also the head nurse in his office) were big believers in these progams and almost every one of my trips to his office (for exams or to diagnose/treat illnesses) meant crossing paths with a teenaged girl in the examination room. The girls received only school credit for the first year (usually their sophomore year), but if they continued with the program beyond one year, they also received a paycheck (a part-time minimum-wage job), with increasing responsibility.
When I was between the 8th grade (junior high school) and my freshman year in high school (I was 14.y.o.), I had to have a complete physical examination prior to attending a month-long military-style summer camp. On the day of my appointment, the doctor's wife/nurse was out of the office when I arrived, so the doctor had their apprentice program participant, "Shanielou", perform most of the tasks that the nurse would normally perform at the beginning of an examination (start a chart/file entry, height/weight, blood pressure, etc), and assist him throughout his examination.
"Shan" was between her junior and senior years in high school (she was 17.y.o.), so she had already completed two years of apprenticeship and was planning to continue with her training/apprenticeship for two more years while attending the local junior college after graduating from high school, and then attend a 4-year nursing college (all of which she eventually accomplished).
I grew up in a very small community, where everybody knew almost everybody else. Shan attended the same Christian high school that I would start attending later that year, and her younger sister ("Shaylynn") had been in the 7th grade at the same Christian junior high school that I had attended earlier in the year. I knew "Shay" quite well, and I recognized Shan when she escorted me and my mother into the examination room. My mother also recognized Shan and asked how her parents were doing (Shan's and Shay's family attended the same church that our family attended).
Shan was VERY professional. She was wearing a nursing apprenticeship unform that she probably hated from a fashion perspetive, but I thought it made her look very sopisticated, in a sexually attractive way. Shan had a job to do, so when we arrived in the examination room, she immediately said, "Okay, I know it might feel awkward, because you know me and I'm only a few years older than you, but you will have to take off your clothes now." Her tone of voice was a mixture of professional/compassionate, but authoritative/stern.
Shan was a very smart (straight-A student), beautiful, and friendly teenager. She was a swimmer in high school and a life guard at the public swimming pool, so I had previously admired how sexy she looked in a swimsuit. When she gave me instructions in the exam room, her professional demeanor, and her white/light-blue striped, neatly-pressed, tightly-fitting, just-below-the-knee sun-dress-type uniform (which buttoned up the front -- her firm b-cup breasts perfectly filling the chest area), emphsized that this 17.y.o. girl was in a clear position of authority over me and my body, in a way that I found very sexy. I desperately wanted to be the one with the authority to instruct her to unbutton that dress and get naked for a physical exam! Having to obey her instructions, esecially in front of my mother, was so embarrassing, but also a huge turn-on for some reason.
So, needless to say, I was rock hard by the time I was naked. Shan said, with a friendly/comforting wink and with a compassionate tone of voice, "Don't worry about your erection. It's completely normal under these circumstances."