Black metal is a pretty slippery beast; some people think it died once Varg got to jail and Euronymous was killed, while others carry on in other veins of black metal. Some people like Watain's frontman Erik Danielsson is of the persuasion that one must live black metal in order to be black metal… which is pretty extreme.
In an interview with DeadRhetoric.com, Erik Danielsson got asked what exactly what makes one black metal and if it goes beyond just the music. Here's what he said to start off the conversation:
"Black metal music is music that, in essence, is diabolical and has diabolical energies and that is where the definition lies to me. Incorporating elements like keyboards… it only takes away from the diabolical aspect of it, because we're talking about the wild, the untamed, ferocious, predatory aspect of it, the tribe within this music. You cannot really get into that permutation with those things if you have a sound that opposes those things."
I can get behind that; the forefathers of the genre sounded like what he's describing. Black metal was all about expression and total hatred, almost revolution in a way against the powers that be (and Christianity in the Scandinavian countries). So far we're on the right track! Then we get a little strange:
"What I can say with black metal is that it's as much about ideology and spiritually and if those things are real, they'll reflect in everything else. Especially aesthetics and the way people appear. For me, the concept of performing black metal in jogging pants and jogging shoes and a Cannibal Corpse t-shirt is impossible; it's not meant to be that way. To me, it's an art form that demands everything. If you want to be in a black metal band, you take yourself as an adversary of society, because that's what black metal is. That has to go beyond just playing songs. That has to reflect on every aspect of your life if you really want to place your focus on this movement."
Well alright then, apparently we've reached the deep end. I get that taking music seriously when you're in a band and believing in what you do is extremely important, but I definitely wouldn't try to be an "adversary of society" and "reflect [it] on every aspect of your life." Some artist's perception of what needs to go into their art varies from others, and I respect Danielsson for taking it that seriously… but damn dude.