Like all songs every listener will interpret it differently.
Black magic-woman could be a black woman who cast magic of any kind whether it be magic that is, black, white or grey, or just evil or good. Or a black-magic woman could be any women black or white.
Black woman are more associated with Black magic and voodoo etc. Caucasian women are more associated with witchcraft and sorcery etc.
The music is a mis mash of blues, rock, african beats and rhythms, latin american, classical and with little bits of things and sounds that were at the time not previously considered to be a part of pop-rock.
Original song by "Fleetwood Mac"
The truth lies somewhere between these three comments.
Fleetwood Mac 'black magic woman'
1.this is great, but a bit dark
basically its a bad woman you just cant resist and you dont care what she does as long as she dosnt leave you cause shes got you so hypnotized that somewhere under there she is worth saving
2.They wrote it in their early days(pre Nicks/Buckingham) and it might even be a contribution from Peter Green or one of the other original members(they've had something like 15 members). Of course, Santana's cover is the version that became famous. BTW, I was told by my grandfather that the "black magic woman" in the song is actually his guitar: a Gibson Les Paul which is, obviously, black.
3.This song is assuredly by Fleetwood Mac. Peter Green wrote it for English Rose, he's given songwriting credit on Abraxas, and it hit 37 on the UK Billboard charts. And you'll observe that nowhere on the Santana version does anyone sing "I want you to love me." Santana breaks into Gypsy Queen instead. In any case, this song's a cool little bit of blues/rock mixed up with some Latin music. Pity Green and Spencer had to totally flip out on acid. I've always figured the lyrics were the standard blues nonsense that just sounds nice and bemoans unrequited love..