Lyric discussion by cpmorgan5000 

Cover art for 13 lyrics by Brian Jonestown Massacre, The

Yes, these lyrics are pretty insane - Anyway, I cribbed this from the web:

"Some say that "13" by The Brian Jonestown Massacre is a tongue-in-cheek song that criticizes hypocrisy and mocks classic rock musicians who dated teenagers. The song may seem like a creepy ode to marrying or grooming a 13-year-old girl, but Aaron Gilbreath of Wondering Sound interprets it as a way to call out classic rock musicians like Jimmy Page, who dated teenagers."

and this article has another hypothesis: https://themusicexperiment.wordpress.com/2012/09/27/song-of-the-week-13-by-the-brian-jonestown-massacre/

[Edit: Incorrect information]