Page 51 of Blood and Hexes

That must have been an understatement: newly made vampires were parched after the change. They needed to get her some blood, and soon.

“And you all smell like dinner.” She didn’t sound surprised, but her visible self-disgust wasn’t unexpected. Mikar had felt the same way about his new thirst for blood when he’d been turned. Most vampires did.

Before he could announce his intention to run to his place to bring her a bottle or two, Gwen had taken the soiled knife discarded on the ground and lightly slashed her forearm. "Here, you can drink from me."

“You might have wanted to clean the blade,” Diana murmured, grimacing.

Tris blinked up at the witch, her expression horrified, but then her eyes darted to the thin line of fresh blood. She opened her mouth, her tongue licking her dry lips. "You don't know what you're offering. I'm literally minutes old. I may not be able to stop myself."

“Whatever.” Gwen shrugged. "There are a bunch of people who will stop you here. You saved Chloe. You're a friend. Friends don't let friends go thirsty."

Tris looked up at Jack, then sat up higher to reach the offered arm. "Watch me," she told her cousin. He nodded, frowning at Gwen, as though he didn't quite approve, but couldn't, or wouldn't, say anything. Not when Tris's well-being hung in the balance.

And then, Tris drank.

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