Cain's valet, Riff is responsible for dressing Cain and tying his shoes, a task that Yuki views as "a form of communication between the two of them because they've been together so long that they're almost like father and child."
Secretly a high-ranking member of Delilah, Riff was placed with Cain to forge a strong bond, ensuring greater pain when he ultimately reveals his longstanding disdain. He had previously murdered his own family and perished in a fire he deliberately set. Resurrected by Delilah and endowed with an alternate, kinder persona, Riff stands as the longest surviving among all the dolls. Periodically brought to the organization’s hideout for blood transfusions to sustain his life, his resolve to defy Delilah strengthened as the hypnosis waned, culminating in him vanquishing his original, cruel personality.
