No, I didn’t say that at all. His statement about these things illustrates his lack of understanding of the topic, which is why I asked if he was familiar with double effect.
Sorry for my misconception.
Why?

In conversation, you assign a meaning that is not morally neutral to words, which are morally neutral. A word is only a combination of vibrations at specific frequencies that are generated by pushing air from our lungs through our vocal cords, nothing more. If our society did not assign a vulgar meaning to it, the f word would not be any more vulgar that the word “Pope.” Music is an art form that uses these frequencies to please the ears. The lyrics are detached from a conversational context, in which metaphor and symbolism are not expected. Therefore, I am free to interpret the lyrics as I wish. Granted, if the lyrics are completely unable to be listened to without invoking vulgar thoughts, then there isn’t really any excuse for listening to the music. There are some songs that I liked so much aside from the lyrics that I learned to strip the vocals from audio files
Well, there are certain principles that are followed after Beethoven, at least, both emotionally and allegorically. Furthermore, I’m speaking of the usage of words that are accepted as vulgar (i.e., in any dictionary that lists it).
I believe I have covered this.
Perhaps, but it would have no bearing on the piece itself. If it incites lust or sinful passions, it would be satanic insofar as it leads to sin. If the author happens to be a satanist and dedicates a song to the devil, that wouldn’t make the song itself illicit. I still wouldn’t recommend supporting such an artist.
That is the real question, and we completely agree on it. If the music incites vulgar or immoral thoughts, don’t listen to it.
I’m basically contending that in this circumstance, it can’t. Words have meanings. Those meanings must be accepted as a relevant circumstance in the moral act being considered. The circumstances make the music evil.
Again, I have covered both meaning and circumstance already.
Note my comment about one of the first principles of moral theology: Bonum ex integra causa, malum ex quocumque defectu. Regardless of any good that may come of such an action, it is still immoral. Again, the very playing of the music is an objective offense against God. It doesn’t matter if no one hears it. You can play it out in the forest with no one around (even you), and it’s still a sin. It is propagating sins against chastity or against the holy name of God or against right order by vulgarity.