[don't worry--sansa would never let it show, but deep down she's eyeing the darkblood smears on his hands (and not only because she'd heard blood was attracting strange bees, lately).]

I can only use my own blood, without a dark bloodstone. It's darkblood magic, you only have to tell the blood cells to move closer together. Have you ever made a snowball?

[necromancy being entirely dependent on dead things makes her a little uncomfortable, in the same way she's not wholly comfortable with magic that requires blood. she'd always only known it in the scary stories her brother and arya liked. but sansa has lived wholly outside her comfort zone before, she's willing to push it a little. especially if it lets her make money out of her own blood for free (and somehow, the bloodstones don't seem as scary as smearing it around in liquid form).]

Everyone has chakra in them, though. It's a word for the energy in living things. Most people can learn to guide it through spells. They're very useful. Paleblood magic is much more concerned with visions and dreams.