Leo was the lone survivor of a bloody massacre.
His loved ones were killed by a group of criminals, he somehow manages to survives.
He later learns that there was a knight in order called 'Black Knights' created by the King, they were knights whose solely purpose was to kill enemies.
The only aim he had in mind at the moment was to train himself so that he could avenge his loved ones. What could be more convenient than joining the the special badge "Black Knights."
In a world where magic is abundant, what challenges will he have to face?
With little knowledge about the enemies, he goes on his journey to avenge.