How do you speak to a vulgar activity while maintaining a pure conscience? It is a very difficult thing to do and it most likely the reason pure minded people are averse to address such issues.
It also is difficult to address these activities as being vulgar because the speaker will be accused of projecting a vulgar image onto a perfectly legimate activity through some particular bias.

The Scriptures set forth an unbiased (being the Word of God) declaration which reveals an eternal value, all time for all men, separating the pure from the impure in a holy manner.

Romans 1:26-32 For this cause God gave them up unto vile affections: for even their women did change the natural use into that which is against nature: And likewise also the men, leaving the natural use of the woman, burned in their lust one toward another; men with men working that which is unseemly, and receiving in themselves that recompence of their error which was meet. And even as they did not like to retain God in their knowledge, God gave them over to a reprobate mind, to do those things which are not convenient; Being filled with all unrighteousness, fornication, wickedness, covetousness, maliciousness; full of envy, murder, debate, deceit, malignity; whisperers, Backbiters, haters of God, despiteful, proud, boasters, inventors of evil things, disobedient to parents, Without understanding, covenantbreakers, without natural affection, implacable, unmerciful: Who knowing the judgment of God, that they which commit such things are worthy of death, not only do the same, but have pleasure in them that do them.