At an academy where individuals who possess a special power known as "Soul Shell" gather, a single boy transfers in. The name of the transfer student is Nanazaki Yuuma.
The majority of those who possess the Soul Shell can manifest it in the form of weapons or armor. However, Yuuma could only manifest his Soul Shell in his right hand and left leg. He couldn't even manifest a weapon.
Despite that, Yuuma displayed overwhelming combat ability without relying on the Soul Shell. In truth, Yuuma's identity was different from the name, age, and data recorded at the time of enrollment. His real name was—Genjurou Magara.
A man who once made a name for himself as a legendary mercenary and vanished without a trace several years ago.
When the "King of Flies" set foot in the academy where boys and girls with special powers attend, borrowing the body of Yuuma Nanazaki to serve as the bodyguard of a certain girl—
The world began to move once more.
This is the story of the strongest man once called "Beelzebuth"—a tale that goes beyond the strongest.
