Lyric discussion by HadjiQuest 

Cover art for Only Skin lyrics by Joanna Newsom

It's obviously about lovers who are in a very strong relationship.

I can't quite make out the way the relationship twists and turns. The song starts with some sort of air... battle? So, I was thinking World War 2, but as the song progresses, the boy grows older and takes up a gun. So, possibly it starts in WWI and progresses to WWII.

The main girl dies....I think? Or perhaps the man dies and then that's what "kills" her. I can't figure that out.

If I had to guess, I'd say that she's some casualty of the war he grew up to fight in. Probably by (fire)bombing.