Misery loves company
Robert Johnson was, by far, the greatest and most influential of the blues singers to arise from the Mississippi Delta in the 1930's. Legend has it that he went to the last crossroads at midnight and sold his soul to the devil in exchange for incredible guitar prowess, but truth be told, as a poor black drifter in the '30's deep south with a penchant for trifling with other men's women his life had enough torment without bnringing in the dark forces.
This song is his most affecting, since along with terror it shows an odd despereate tenderness. Over his incredibly intricate guitar and in harrowing voice, Johnson the infamous bad man invites an ostracized paramour to come into his home. Both parties are plainly in for little good in this world and not much good for eachother, but they're the ones who will take eachother in. In more clinical language the situation so chillingly portrayed here could be called 'codependence' but another way of putting it would be 'bonded by doom.'