Sebastian Michaelis (セバスチャン・ミカエリス, Sebasuchan Mikaerisu?) is the butler of the Phantomhive household and acts as Ciel's bodyguard. Sebastian often describes himself through his catchphrase "I am merely one hell of a butler" (私はあくまで執事ですから, Watashi wa akuma de shitsuji desu kara?). The phrase plays on the word "demon" (あくま, akuma?) and the phrase "to the end" (あくまで, aku made?). It can also translate to "I am a demon and a butler".
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