Stroke 9: Little Black Backpack

I'm not sure I know what these words are about, but I like the song anyhow. My take is, the couple who's tight in a lot of ways, but one night at the bar she's too friendly with someone or someones too friendly with her, etc. Hopefully the make up sex produced a good song , too. "Your mind is lined with layers of lead..." is my favorite line.
Moot Pt.

I know it
It's a shame
A shame I can't show it
And I see it
I can see it now
But I'm so far below it
Don't wanna

Don't wanna talk about it
I say why not?
Don't wanna think about it
I say there's got to be some good reason
For your little black backpack
Up, smack, turnaround he's on his back
And
Don't wanna tango with you
I'd rather tangle with him
I think I'm gonna bash his head in
And this shouldn't concern you except that
Just don't expect to get your bloody black backpack back

I feel you
Yes I can
What about that don't you understand?
I sense you
It's something sensual
But it's less than I planned
Don't wanna

You're trying to find a reason for the way you feel tonight
Your mind is lined with layers of lead
Have you heard one thing that I've said?