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.
Touya Mochizuki was accidentally killed, and as an apology, God allows him to be reborn in a fantasy world and will grant him any one wish he desires. And so, Touya chooses to keep his smartphone in the next world. In his second chance at life, he befriends many important figures and comes across the world's secret. He inherits the legacy of an ancient civilization and travels around nonchalantly while possessing powers that rival this world's kings.