Rokurō Wakamura/Plot

Background
Wakamura enlisted in Border approximately two years before Chika Amatori and Yūma Kuga. He joined Katori Squad through his friendship with Katori's brother. At some point he was tutored by Sumiharu Inukai in Gunner techniques.

Introduction Arc
Katori Squad presumably takes part in the extermination of all Rads in Mikado City.

Round Three
On Saturday February 8, Katori Squad fights in the day division of rank battles against Ōji Unit and at least one other team, ranking sixth at the end of the match. After the points from the night division are tallied, Katori Squad drops to the middle tier of B-rank for the first time in two seasons.

Round Four
Katori Squad drops to 9th place after their defeat at the hands of Nasu Squad.

Galopoula's Invasion
Katori Squad is on defense duty on Wednesday, February 19 and they make short work of a group of Marmods. When Yōko Katori complains about having defense duty on the day before a match, Wakamura retorts that it happens to all units and that she should watch the logs before complaining. The two begin to bicker until Hana Somei rebukes them.

Round Five (Night)
Minutes before the match Wakamura looks over Tamakoma Second's files while Katori plays on her phone. He calls her out on becoming apathetic every time they lose, criticizes her for never making an effort and dropping anything that challenges her. She demeans his skill in turn, but he retorts that precisely because she is so much better than he is, she should stop quitting before even making an effort. Katori rudely dismisses him, and the rank battle begins. Katori goes after Yūma right off the bat, to Wakamura's frustration. Yūta Miura and he rushes to support her, activating their Chameleon as they make their way towards Osamu Mikumo. Wakamura arrives just in time to protect Miura and Katori from Osamu's bullets. Katori warns him that Yūma is coming and Wakamura turns to intercept him, but the Attacker uses the invisible wires set by his teammate to dodge and nearly takes Wakamura out. He blames Katori for the damage they suffered, sparking a short discussion with her before they attempt to flee the wire zone. Wakamura attempts to cover their retreat, but he struggles to read Yūma's movements.

Tamakoma Second stops chasing them as soon as they leave the wire zone, but Kakizaki Squad is immediately onto them. When Kotarō Tomoe disrupts their formation, Kakizaki Squad gains the upper hand. Wakamura prevents Katori from charging head-on, but their defenses are gradually whittled down. Somei recommends moving to an open area to force Tamakoma Second, whom they know to want to score as many points as possible, to come to their aid. The combined fire prompts Kakizaki Squad to retreat and all three units separate to regroup. Wakamura reproaches Katori for acting on her own, which led to Miura, and he taking damage to protect her. She retorts that they protect her because they would be unable to win without her. After their squabble, Katori suggests ignoring Tamakoma Second and fighting Kakizaki Squad outside of the wire zone, with Wakamura approving of her plan and proposing an ambush. As the two units begin to converge, however, Chika starts to demolish the surrounding structures.

Wakamura is surprised that Katori does not know about Chika's firepower. Somei tells her teammates that they should ally themselves with Kakizaki Squad and go into the wire zone to pressure the Sniper with their numbers. Contrary to their expectations, the one who intercepts them is Osamu. Katori Squad makes their way to him while cutting down his wires, until their chase takes them to an area to which Chika has a direct line of sight, forcing them to take cover against her Lead Bullet sniping. Katori rejoices when Tomoe bails out, but Wakamura points out that if Kakizaki Squad falls, Yūma will come after them next. Katori Squad convenes not to take a detour but to take out Osamu first. Wakamura attracts Chika's attention while Katori and Miura charge at the enemy Shooter, but their offensive fails. Wakamura realizes that Tamakoma Second has anticipated all their moves.

Katori Squad is forced to shoot at Osamu from behind cover, essentially being stuck in place as they cannot understand how Osamu managed to make Katori trip. When Kuniharu Kakizaki bails out as well, Katori takes her frustration out on Wakamura. Somei tells her to distract Osamu while Miura and Wakamura circle around him, the former using Chameleon, the latter Bagworm. Wakamura trips as Osamu produces more red wires, and is taken out by his planted bullets.

When, after the end of the match, Katori has a meltdown, Wakamura is flabbergasted by Somei's incitement to her captain to quit Border, and even more so when Miura speculates that the reason that Katori is so angry is that she envies Tamakoma Second.