Looking for story where inexperienced couple goes to sex doctor

[acd1969]

Here's what I remember: The story premises around a married couple that is not having satisfying sex going to a sex doctor together. They are both extremely inexperienced with sex despite being married. Once they arrive, the man is surprised that he is assigned a doctor who is a woman and the woman is surprised to be assigned a doctor who is a man. As you can imagine, each respective doctor teaches their patient about the joys of sex and how to please their partner. I specifically remember the wife's doctor teaching her that she can turn a penis into a cock by rubbing it.

Any help in locating this is greatly appreciated!