Evelyn worked - as it happened - in a fertility clinic behind the college campus. I only realised it was a fertility clinic when she invited me there one afternoon after classes.
She told me - very business-like as always - that there was a shortage of high quality sperm. Whether I would consider donating? It would be pro bono as was the clinic, but she would try and make it worthwhile in other ways. She obviously had first hand knowledge that I both produced ample volumes of the stuff and that it had a pleasing taste. However, it would be necessary to check the qualities more relevant for fertility. She asked me to provide a sample then and there for testing. How could I not agree to this.
Things progressed quickly from there. We were already in the consultation room. She asked me to strip to the skin and wait as she retrieved a colleague. A few minutes later she returned with a stern looking female doctor. She was older than Evelyn, tall, with jet black hair in a pony tail. Large fashionable glasses. She looked busy and every bit as business-like as Evelyn. She took no notice at all that I was stark naked.
"Hello, James", she said. "I'm Dr. Callahan - I'm the head fertility doctor here. I'm so happy to see we can still attract new donors. As I'm sure nurse Vaughn has told you we need all the sperm we can get. More and more women and couples are seeking our assistance - and we have trouble competing with commercial clinics that are able to pay their donors. Your contribution is most welcome." She smiled very professionally. She glanced in the direction of my dick, which was getting fatter as she spoke.
"However, we must test the quality of your sperm, obviously. As it's supposed to make some lucky women pregnant." She smiled again, this time not bothering to hide that she was having a good look at my cock. "I know you are in good hands with nurse Vaughn - she is our most experienced and trusted expert in these matters." She sat down behind the desk and consulted the screen, punching something in once in a while.
"So, how long since your last ejaculation, mr. James?" She looked up.
"This morning." Evelyn replied. "Twice."
Dr. Callahan grinned broadly at her. Then she looked more seriously in my direction.
"Well, that's quite recent. Normally I'd say come back in three days. But we are pretty anxious to get started. What do you say, nurse, should we try the new serum in this case?" She looked back at Evelyn.
"Absolutely", she replied. "My sense is that in this case it would be quite worthwhile." She didn't look at me at all.
"Quite." The doctor nodded. "Would you set up, nurse? Thank you." Evelyn left to make arrangements.
"So, mr. James, nothing to worry about.", the doctor said. "We have contrived a little cocktail to accelerate semen production. Although still experimental, it's perfectly safe. The question is only whether it works or not in your case. Therefore, we shall administer it, but also take the opportunity to monitor how it works. Hopefully, you will be able to deposit a sufficient amount already tonight. You'll see." My cock was now in full salute, not that it seemed to distract the doctor the slightest.
Evelyn returned with a cup of the serum. It looked like semen to me, only slight bluish.