Black Butler: Public School Arc Episode 9 English Dubbed Episode Title: His Butler, Having a Laugh Episode Description: Derrick attacks Herman, taking a bite out of his arm, and Ciel summons Sebastian to restrain him. He realizes that Derrick was transformed into a reanimated corpse like those they faced aboard the Campania. The principal reveals himself as Undertaker in disguise, affirming that he'd been toying with Ciel and Sebastian. The four prefects confess that Herman killed Derrick months ago and they sought help from the Aurora Society to cover it up. Derrick, who was Redmond's fag at the time, was assigned to investigate complaints of bullying occurring in the school, only for the prefects to discover that Derrick himself, along with four of his friends, were the culprits, tormenting and assaulting their schoolmates.