Sebastian Michaelis is the demon butler of the Phantomhive household. He often describes himself through the phrase "Because I am simply one hell of a butler" (わたしはあくまで執事ですから, Watashi wa akumade shitsuji desu kara). The phrase plays on the word "demon" (あくま, akuma) and the phrase "to the end" (あくまで, akumade). It can also translate to "I am a demon and a butler." Sebastian is highly skilled in any area and handles every task, no matter how impossible it is as well as any problem that arises from the errors of the other staff with ease, stating it is only natural as the butler to the Phantomhive family. This is due to the fact he is a demon bound by a Faustian contract to abide by Ciel's will. A sign similar to the one marking Ciel's right eye can be found on Sebastian's left hand, which has been used on one occasion to twist the arm of a kidnapper without touching him.

Second year in Kasensou Private Preparatory Academy. Childhood friend of Rintarou's, and slow by nature. Speaks in a very wavy manner, and seems to always be smiling and having fun. She's quite the optimist. She has trouble understanding complicated theories, but doesn't mind as long as it's enjoyable. Doesn't like people arguing, and is depressed when things are unpleasant. Though she'd like to ease the situation in such cases, she's not really good at reading between the lines. She often went with her grandmother to see the stars on her grandmother's back. Because of that, she has a habit of reaching her arm out to the sky at times, which has led Rintarou to naming it the "Stardust Shakehand." She abruptly does this (even if she's talking with someone), which surprises everyone around her.