Akira Udou

Akira is imposing and serious, but his motives are more complicated than Behemoth's predatory reputation initially suggests. He values strength and surrounds himself with riders capable of overwhelming teams that expect a normal D-Class opponent.

His relationship with Agito mixes friendship, rivalry and resentment. The two understand one another as Bloody Road riders in a way few others can, making possession of the Fang Regalia both a personal and technical dispute.

Akira is also capable of recognizing defeat. Once the confrontation with Kogarasumaru resolves the question of the Fang Regalia, he does not continue Behemoth merely to preserve his pride.

Akira follows the Bloody Road and is a King-level rider. During the Behemoth battle his R.E.A.D. level reaches 100 while using the Fang Regalia, compared with Agito's 99 without it.

His immense physical strength is associated with myostatin-related muscle hypertrophy, the same condition found in Mitsuru Bando. Akira's muscle fibers are dramatically denser than normal, allowing him to overpower exceptionally strong opponents physically.

Gigaer Cross fires two Fangs simultaneously in a cross-shaped pattern. Cage of Fangs surrounds a target with intersecting pressure blades, compensating for the Bloody Road's difficulty against highly mobile aerial opponents. Akira can also produce concentrated Solid Fangs.

His custom Gigaer Air Trecks are designed around the Fang Regalia's core. Their modifications increase the system's combat performance at the expense of ordinary functions such as jumping.

Akira forms Behemoth after leaving the Windstorm G-Men and gaining possession of the Fang Regalia. Although officially D-Class, Behemoth deliberately avoids promotion so it can prey on lower-ranked teams while fielding riders far above that classification.

Kogarasumaru's confrontation with Behemoth culminates in the dispute between Akira and Agito. Akira's experience with the Regalia initially gives him a significant advantage and demonstrates how dangerous the Bloody Road becomes when paired with equipment optimized for it.

Agito and Ikki ultimately defeat Akira, after which he returns the Fang Regalia, dissolves Behemoth and rejoins the Windstorm G-Men.

Akira later attempts to assist Spitfire and Aeon Clock against the Takeuchi brothers and is badly injured. He subsequently remains connected to the riders opposing Genesis and helps Kazu through the aftermath of Spitfire's loss.

Agito Wanijima is Akira's former Windstorm G-Men colleague, close friend and Bloody Road rival. Akira takes the Fang Regalia after defeating him, but later returns it after losing to Kogarasumaru.

Kaito Wanijima commands the Windstorm G-Men and regards Akira as a trusted subordinate after his return to the unit.

Mitsuru Bando, Yasuyoshi Sano, Ryō Mimasaka and Fūmei Goshogawara are the elite riders operating under Akira in Behemoth.

Itsuki Minami joins Agito Wanijima in the confrontation that ultimately defeats Akira.

Kazuma Mikura receives Akira's support after Spitfire's death leaves him emotionally devastated.

Ren is Akira's romantic partner.