Flail serves the Knights of the Ashen Flame while conducting a deep cover infiltration within the 3rd Special Fire Force Company. His mission involves gathering intelligence and advancing his primary organization's goals from inside the firefighting unit. Three years before his known activities, Flail crossed paths with Akitaru Ōbi, later Captain of Company 8. This occurred while Flail maintained his firefighter facade, his true allegiance always lying with the Knights. In combat, Flail wields pyrokinetic abilities to generate and shape flames into a spiked iron ball. This fiery construct serves dual functions as a blunt force weapon and a ranged projectile, demonstrating his offensive specialization in flame manipulation. A pivotal confrontation unfolded between Flail and Maki Oze within the Netherworld. During their battle, Flail delivered a taunting remark aimed at Maki's appearance or fighting style. This provocation ignited intense fury within Maki, a key factor leading to Flail's defeat in that encounter. Flail's location, activities, and allegiance following this defeat are unconfirmed. His ultimate fate remains unresolved within the documented narrative.