Jutto Sego is the reincarnation of the Warrior of Light, a central figure among ten legendary warriors who originally sealed the Demon King in feudal Japan. His destiny is to prevent the demon Lord Shindigan from resurrecting the Demon King in the present day. Initially, Jutto resists this role while living as a student at Fuuin High School, displaying reluctance when other reincarnated warriors recruit him. His personality is stubborn and abrasive; he frequently dismisses or yells at his supportive teammates during battles against the Kyouma demons. This resistance stems from skepticism toward his predetermined destiny and the group's hierarchy.

He wields potent light-based powers that become increasingly vital to the group's combat effectiveness. His abilities often surpass those of the other warriors, leading some teammates to explicitly acknowledge him as the indispensable "hero." Jutto typically operates independently, preferring to confront threats alone rather than collaborate, which strains group dynamics but underscores his pivotal role in critical engagements. His relationship with Kokono Kifu, the warrior who summons sacred beasts, is significant but underdeveloped, marked by tension and jealousy when she aids others, though neither openly expresses deeper feelings.

During the final confrontation against Lord Shindigan and the Demon King, Jutto's powers prove decisive. He confronts the primary antagonists directly while several other warriors are sidelined or absent, cementing his indispensable role despite his earlier resistance. The narrative concludes with Jutto and the surviving warriors implying an ongoing duty to combat demonic threats, with his personal acceptance of this responsibility remaining implicit.