how do you even do that hair thing and shade a thing when it basically blends into the background??

do you just say "screw it, the light source is not in front of you now"?

as I said before... hair in an asshole

ooooooohhhhhhhhh..... that's how you do that even in crisp dark shots... you have to differentiate it with color otherwise the definition is lost and it oooooohhhh... there we go...

and hair when it's black on black will need a crisp reflective line too? hmmmmm

yeah... i just picked a poor reference picture