Task: Question Answering
Input (English): Passage: William "Bill" Boss, a psychopathic prison warden, watches the end of The Human Centipede 2 (Full Sequence) with his accountant, Dwight Butler. Bill says that he hates the films as his feet are massaged by his secretary, Daisy. Daisy replies that she enjoyed them. In response, Bill sucks his finger and inserts it into Daisy's vagina, telling her that women should not be allowed to voice their opinions. Dwight interrupts, attempting to pitch a "brilliant idea" to fix the prison's horrible retention and violence rates, but he is interrupted by a phone call.
Bill and Dwight are then summoned to the scene of an assault within the prison. One of the officers has been stabbed by an inmate. As punishment, Bill decides to stomp on the arm of the prisoner, exposing the bone and causing immense pain. He promises to do it again when his bones are healed.
Back in the Warden's office, Bill receives a mysterious package. After Dwight asks what it contains, Bill reveals that it is a jar of specially imported, dried African clitorises which he eats "for strength." After eating a few, he receives a threatening prank phone call from one of the inmates. Bill waterboards him with three buckets of boiling water, horribly disfiguring him. The inmate tells Bill that he has lost his soul.
Governor Hughes arrives immediately afterwards, ordering Bill and Dwight to put a stop to the violence and promising that they will both be fired otherwise. In anger and retaliation, Bill orders a 'mass castration' of the inmates, and castrates one of the prisoners himself. He covers his face in the blood of the inmate and later eats the cooked testicles for lunch, calling it "Energy Food." Daisy is forced to perform fellatio on Bill while Dwight is in the room. Upon completing the act, Daisy eats one of the dried clitorises, mistaking them for candy. 
Question: What is the last name of the person who is interrupted by a phone call?
Output (English): Butler.