Grayson is a young man who was possessed by the Dark Sword; Masamune. He is one of the only humans to have survived the effects of having Masamune stripped from his soul. Grayson maintains remnants of Masamune's power and is able to control the Madness harnessed from its Dark Abilities.
Child of Madness
Grayson was a young man living in Stimo Village until it was found that the Demon Sword; Masamune was located near his home. While good and evil searched for the blade, it attacted itself to the soul of Grayson. It used his body to fight off its pursuers but was eventually captured. The blade was stripped from Grayson's soul but its power of Dark Madness lies dormant within Grayson. Its evil temptation has led him to join the Dark Guild Achluophobia.