"Those guys divided the whole body and the limbs. In other words, those guys stole, more than her hands or feet, her vampire existence. For this reason the four limbs won't regenerate nor vanish. As a matter of fact they have been paralyzed. By suppressing the vanishing, you forbid the regeneration -- thinking about it, for sealing the Kaii Killer it's a very effective tactic."

(Kizumonogatari, ch. 9)