Gaku is a major antagonist in Sakamoto Days. He is a powerful assassin under Slur and aids him in overthrowing the JAA.

He is a tall man with light-colored hair styled in a slicked back manner.

He wears a pair of black square-shaped earrings, a high collared black jacket with the sleeves rolled up, bandaged hands, black baggy pants, and strapped sneakers. He can often be seen carrying a cube-headed mace covered in wrappings over his shoulder.