Laura

An assassin, skilled with firearms and other weapons, who is repeatedly sent to assassinate Rin by Apos. Although Rin kills Laura in every engagement, Apos resurrects her so that she can attack her again. In episode four, she becomes a cyborg, though the extent of her transformation is left open. Episode five reveals that Laura was originally an immortal but was captured by Apos who keeps her real body restrained while she remotely controls an android designed to resemble Rin. In episode six, she reveals that only her brain is immortal, as Rin extracts the Fruit of Time from there. (Source: Wikipedia)