Blood was magic made manifest. There it thrived. And there it poisoned. Kell had seen what happened when power warred with the body, watched it darken in the veins of corrupted men, turning their blood from crimson to black. If red was the color of magic in balance---of harmony between power and humanity---then black was the color of magic without balance, without order, without restraint.
V.E. Schwab, A Darker Shade of Magic
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