I'm not concerned about discussing the lyrics to Closer (for one example) with my teen.
I'm concerned about my teen finding Closer in my collection and thinking "Uh, Mom? WTF!"
A song like 'Closer'? That would definitely be in the very uncomfortable category, so I would just avoid it altogether. But I know exactly what you mean, and I do wonder how it will affect how my daughter sees me. I imagine the 'mom and sex in the same sentence' gag reflex will make it a little self limiting. I certainly didn't associate that world with my mom, when I was growing up.
There are some other things to consider. One is just simple swear words. My 15 year old daughter thinks it's cool that dh and I listen to loud rock n roll with swear words. She used to be scandalized. Seriously, our kids used to scold us for play that music too loud.
I don't always listen closely to lyrics. Once when I was doing the rounds and picking kids up from school I had Rage Against the Machine blasting. All of sudden ds yelled, "MOM! You might want to turn the music down!", and I realized we were at the point in "Killing in the Name" where he screams F- you, I won't do what you tell me!!! about a hundred times (maybe it's only eight times).
The other thing is sexual explicitness (a little gentler than 'Closer'). And I kind of treat music the same way I treat certain movies, where my kids are concerned. It's been interesting navigating certain sexually charged scenes in movies with our teen daughter. It's just plain uncomfortable and squirmy. So I acknowledge that it's uncomfortable and we laugh about it. We avoid watching certain movies with her, even though I don't particularly object to her seeing those movies.
And then there's sexually explicit lyrics that sexually degrade women. That I don't tolerate. And I told my kids, I don't care about swear words in music. I just would be very unhappy and disappointed if you got into music that exploits and degrades women.
I think about this often, because in regards to pop music and pop culture in general, I do think there's a difference between what I experienced growing up with my parents, versus what my kids are experiencing with dh and me. My parents were from the Benny Goodman, Frank Sinatra era. They thought the whole hippy, rock n roll movement of the 60s and 70s was a disaster. They were of the 'turn down that damn music!' era and they didn't like that I listened to anything of a sexual nature. So I was a rebel simply by listening to FM radio, and the divide between the generations was firmly established in my mind.