Hiro Kitazoe/Plot

Background
Kitazoe joined Border approximately three years before Chika Amatori and Yūma Kuga. He came to a mutual understanding with Masato Kageura after eight rounds of solo battle. At some point Kageura Unit was formed and climbed to A-rank no. 6, but it was demoted when Kageura threw an uppercut at Eizō Netsuki.

Introduction Arc
Kageura Unit presumably takes part in the extermination of all Rads in Mikado City.

Large-Scale Invasion Arc
Due to Masafumi Shinoda preventing B-rank units with missing members from fighting against Aftokrator's forces out of fear of capture, Kageura Unit was not deployed.

Round Four
On February 11, Kitazoe and Yuzuru Ema find their captain watching the log of Yūma's fight against Kō Murakami in round four, prompting them to note that it is rare for him to do so. Convinced that he has finally found his motivation, Kitazoe's eyes well up with tears, adding to Kageura's annoyance. Four days later, during the night division of rank battles, the match between Kageura Unit, Ninomiya Unit, Azuma Unit and Tamakoma Second begins in a snowy Cityscape B. Kitazoe spawns to the north-west of the map and immediately climbs atop a building to bombard all trion signatures within range; however, none of his attacks connect. Before he can target the possible hiding places of the members of Azuma Unit, Masato Kageura fires back with Asteroid, forcing him to flee. The Gunner asks for Ema's help, but when his Eaglet is easily blocked, Ema leaves his teammate to run from the chasing Ninomiya by himself. Kageura also ignores the fact that Kitazoe is holding up the dreaded Shooter so he can have his fun with Yūma.

Ninomiya eventually switches targets from Kitazoe to Ema, which the Gunner discovers only when his teammate is attacked and bails out. Now unmarked, Kitazoe aims a few rounds of Meteor at the area where the Attackers of the four units are fighting, but to his shock they are detonated mid-flight by Haruaki Azuma, who proceeds to target him next. Kitazoe is however saved by none other than Ninomiya, who wants to claim the point. Resigned to his fate, Kitazoe uses his last moments to bombard the Attackers, providing crucial assistance to Kageura, before bailing out. When only Azuma, Kageura and Ninomiya are left, Kitazoe and Nire pressure their captain into staying hidden until the end. Time runs out without further developments and Kageura Unit ties in second place with Azuma Unit.

Round Five
On February 19, the night of Galopoula's blitz, Kageura Unit fights a rank battle against Azuma Unit and Yuba Unit.

Round Six
Kageura Unit fights against Ninomiya Unit, Azuma Unit and Suzunari First in the night division of the sixth round of rank battles. Kageura Unit and Ninomiya Unit tie at the top with three points. No unit receives the survival bonus due to there being multiple survivors. Following the match, Kageura Unit remains in second place with a point total of 34.

Round Seven
Four days after the blitz the members of Kageura Unit, Murakami, Yūma and Isami Tōma dine at Kageura's family's restaurant. Tōma and Kitazoe agree that their host has taken a liking to Yūma, the thought of which and of Ema having a crush move the Gunner to tears. When Kageura reveals that Ema intends to throw the match for Chika's sake, Kitazoe voices his doubts that they would be able to win that easily if he didn't. He follows Tetsuji Arafune's intervention with interest. When Ema leaves to review Tamakoma Second's logs following Yūma's confident declaration that they will win, he expresses his fears that the Sniper would have been penalized for letting his opponents win, although Tōma disagrees, citing Chika's inability to shoot others. Yūma is unwilling to confirm their deductions until Kitazoe corners him. The Gunner is relieved, as she would otherwise be unstoppable with her trion, but Tōma explains that being unwilling and unable to shoot are two different things. After dinner, Kitazoe drives Yūma home on his motorbike.

Over the few days before Kageura Unit's match against Tamakoma Second, Azuma Unit and Suzunari First, Kitazoe happily watches the logs of their upcoming opponents with his teammates. When March 1 arrives, Kageura is surprised by Tamakoma Second's addition of a new fighter, whom Kitazoe does not recognize. The stage chosen by Suzunari First is revealed to be Cityscape D, which the Gunner takes to mean that they want to hole up in the mall and evade the Snipers, to which Ema adds that it also counters Kitazoe's own Random Meteor. Kageura and Kitazoe do not feel at a disadvantage in a close-quarters encounter, unlike Ema. Kitazoe and Nire worry about him being hindered, but the decides to enter the mall and fight at Gunner range, impressing them with his resolve.

Kageura spawns on the fourth floor of the mall and begins to move upwards as Kageura climbs to the roof. The map is revealed to have a nighttime setting. Kitazoe notices that someone on a lower floor is chasing after him, and infers that it must be an ace. As Ema informs him that he will not be able to reach them for a while, Kitazoe spots and fires at his pursuer, who turns out to be Murakami. He meets up with Kageura on the sixth floor just as Tatsuya Kuruma reaches his own teammate. A firefight begins which the two Attackers soon join. Though Kageura Unit appears to have the upper hand at first, the tides turn when Kuruma shifts into Full Attack. Kageura chooses to fall back, surprising Kitazoe. They take shelter inside a restaurant, the narrow space preventing Kuruma from using his pincer attack, but just as they seem to be regaining the upper hand, Taichi Betsuyaku turns off the lights in the mall. Kitazoe is forced to suspend his cover fire not to hit his teammate, until Nire activates visual support. However, Betsuyaku switches the lights back on, blinding Kitazoe and Kageura and allowing Murakami to land a heavy hit on the Attacker. When Ema's attempt to destroy the fuse box fails, Kitazoe shoots the light fixtures and tries to calm Kageura.

However, Betsuyaku bails out moments later, and the fighters move outside the restaurant just as Hyuse and Yūma arrive. The duo from Suzunari First moves away while Kageura Unit and Tamakoma Second prepare to clash. Hyuse walls Kitazoe off from Kageura with Escudo, turning the battle into a two versus one. Kitazoe kicks down the walls and manages to reach his captain an instant before Tamakoma Second can deliver the final blow, only for Hyuse to trap him. When he sees Yūma coming, Kitazoe conjures his grenade launcher and shoots the ground just as the enemy ace beheads him. Yūma survives the explosion, but Kageura uses the opening in the floor to survive long enough to give the point for his own defeat to Suzunari First, for which Kitazoe congratulates him. When Ema also bails out, Kitazoe praises his wall-piercing sniping. At the end of the match the members of Kageura Unit listen to the commentators' final remarks. Taking note of Kageura's wistful demeanor, Ema asks Kitazoe if he is alright, with the Gunner telling him that he was nervous due to the Sniper's participation in the away mission riding on their success.

Round Eight
On March 5, Kageura Unit faces off against Ōji Unit and Azuma Unit in the day division of rank battles. Azuma Unit wins the battle, which took place in Exhibition Hall, with a final score of 4-3-3.