Image: Rebel Wolves / Bandai NamcoOfficial screenshot from Rebel Wolves / Bandai Namco.
Nourishing Blood is a night-only Vampirism perk that makes feeding heal Coen more. It is a cheap way to make Voracious Bite a real healing tool in fights.
Every time Coen drinks blood, he gets back more health. That includes feeding with Voracious Bite in the middle of combat.
Night only, like the rest of the Vampirism tree.
Voracious Bite, which lets you feed mid-fight. Feeding also raises Corruption, which unlocks the higher ranks of this perk.