The word the Church often uses is "counterfeit." I like the term "mimic" too. I think both work well. From what I have understood of Pope John Paul the Great's earlier work Love and Responsibility, I think mimic is a good translation of what he is describing for the sexual activity that happens in a counterfeit of marriage. I still struggle with that book. It is a very difficult read. A theologian friend once said, "When I got stuck I started counting the words in a paragraph. There were 100 words. And it was one sentence! And it wasn't a run-on!!" I have little kids so I can be easily distracted. I don't stand a chance until they are older.
When I was really introduced to the idea of sexual counterfeit and sexual mimic, the remaining questions I had about the morality of sexual acts finally became clear. Until then, I couldn't distinguish a definite line between things that our culture crudely calls, "oral sex," from the beautiful overture to the marital act known as foreplay. On Catholic bulletin boards I would see people dancing around the topic, and then using all sorts of strange authorities, or even popular, well known speakers, to try to justify their point of view. None seemed like sound answers.
It became the last piece of the puzzle I needed to answer for me. What really is the difference between immoral "oral sex," compared to moral, oral stimulation during foreplay? I found my answer as I read more deeply about the word counterfeit. A small blip in my mind gave me the clue, "mimic." That word, mimic, became very important. I asked my husband about it. We talked frankly about our pasts again, like when we were first dating. I asked friends and really started to examine the idea. And most importantly, I contemplated my own marriage act itself compared to my past sexual encounters. That word summed it up. Mimic. It was in using sexual acts that mimicked foreplay, that I first began a counterfeit sexuality in my past.
In reading and hearing Catholics try to defend oral sex as moral on one end of the spectrum, fighting with other Catholics at the other end of the spectrum, who couldn't even comprehend the idea of foreplay; I knew there had to be a way to objectively determine what is and what is not a moral sexual act. I was going out on a limb in saying that oral sex was not moral even when "used as foreplay," as some popular theologians have claimed. But at the same time, I didn't want that limb sawed off by a person saying that foreplay was oral sex since it sort of "looked like oral sex." There had to be an objective line. I found it in that one word. MIMIC.
I looked at the design of the body again. The mouth, the hands, the sexual organs, the reproductive organs; they all have a design. They all have a purpose. The mouth is designed to taste and suckle. The kiss is built right into the design. There is not a single spot on our spouse's body that we are forbidden to kiss, and to suckle. Where the line crosses into the counterfeit acts is in an act that mimics. The moment the mouth ceases to behave as a mouth is designed to, and instead mimics a genital, it has become a counterfeit act. When the hands and fingers cease to caress and guide, they are counterfeits of their design. When the hands mimic a penis or mimic a vagina, the act has degraded into a mutual masturbation. There is a difference, and that difference makes an enormous change.
I found that when I stumbled on to that truth, my own marriage got even better. I found that intuitively, the acts that never quite "felt right" were mimics. They were a poor substitute for the real thing. Clearing out those acts intensifies the anticipation. Foreplay is really something for before, when the mimic is removed. When the mind-blowing climax follows it is just as many people have described, "The closest we can get to feeling in heaven, while still alive."
Marriage is the first step to overcoming any mimic. Fornication is defined by its "counterfeit-ness." In fornication, two become one, but only for today. Tomorrow, they go their separate ways. The next steps are in truly bringing your marriage to God through prayer and sacrifice. He designed sex. He is the author, therefore, the ultimate author-ity. The final steps are in the communication between spouses. Communion has many meanings. All are important to marriage.
I have asked many times, "what could have been said to me waaaay back when, that would have helped me wait for marriage?" I have found that the idea of mimic and counterfeit would have been the most compelling arguments for me. If someone had told me, that fornication, contraception, and oral sex were the sexual equivalent to inheriting a fortune, only to find out it was counterfeit money in the end; I would have made different choices. I mean, really. Who wants to roll around in a big pile of counterfeit?