In Victorian-era London, on the night of Ciel Phantomhive's tenth birthday a fire destroyed his manor and killed both of his parents. In a moment of death Ceil strikes a deal with a demon, his soul in exchange for revenge. This demon becomes his butler and calls himself by name of Sebastian Michaelis, to protect and serve Ciel until the deal has been completed. One month after the fire Ciel returns from being missing, with his new butler Sebastian. Ceil is now the head of the Phantomhive corporation, handling all business affairs as well as the work as the Queen of England’s guard dog and looking for his parents murders.
The story follows Issei Hyōdō, a dim-witted, lecherous second-year high school student who is killed by a girl on his first date ever. Issei is reincarnated as a devil, and from that day forward, he serves as an underling of Riasu, a high-level devil who is also the prettiest girl on Issei's campus.
Sonya is an assassin attending a normal school. Yasuna is an airhead who follows Sonya around, unaware of how dangerous she is. This adaptation of a 4-panel comic focuses on the adorable ultra-violence that erupts when they try to get along.
Haruka Takayama and Yuu Sonoda were inseparable during their junior high school years, but upon entering their senior high school, they end up being seated on opposite sides of the classroom. Having to spend time with more friends, the two decide to do something to make their relationship special.
Right after starting middle school, Akari Akaza joins the Amusement Club which is composed solely of her two childhood friends, Kyouko Toshinou and Yui Funami. Chinatsu Yoshikawa, Akaza's classmate, becomes a member after finding out about the dissolution of the Tea Club. The Amusement Club, situated at the tea room facility since the Tea Club disbanded, has no clear purpose, being free for the girls to do whatever they want.