Tatsuya Kuruma/Plot

Background
Kuruma hails from a rich family, who spoiled him growing up. He joined Border approximately two years before Chika Amatori and Yūma Kuga, and his family donated to the organization the building that would become the base of Suzunari Branch.[BBF Q86] Kuruma used to keep an aquarium in Suzunari Branch, but after Betsuyaku accidentally boiled all the tropical fish inside to death no new aquaria were installed.[BBF Q89] On another occasion Kuruma gifted Taichi Betsuyaku a hat out of concern for his clumsiness.[BBF Q90]

Around eight months before his unit's match against Nasu Unit and Tamakoma Second, Kuruma found Kō Murakami crying in a corner. Murakami blamed himself and his Side Effect for Tetsuji Arafune abandoning the Attacker class. Kuruma thus cycled to meet Arafune, who told him he had always planned to change class after reaching 8000 points, his ambition being to become the first Perfect All-Rounder after Reiji Kizaki and to develop a master theory that would allow the mass production of Perfect All-Rounders. Kuruma then taped a video with Arafune to put his teammate's mind at ease.

Introduction Arc
Suzunari First was presumably involved in the extermination of all Rads in Mikado City.

Large-Scale Invasion Arc
Suzunari First is deployed by Masafumi Shinoda to prevent the initial wave of Trion Warriors sent by Aftokrator from reaching Mikado City. Border's traps buy them enough time to arrive on the scene, and Kuruma reports the successful suppression of the Trion Warriors. When a Rabbit emerges from a carcass, however, Murakami tells an intimidated Kuruma to step back. Suzunari First attempts to meet up with Haruaki Azuma, but the Rabbit continues chasing them, until Murakami volunteers to take it on by himself while his teammates meet up with the other B-ranks. When Lamvanein targets them, Kuruma is shocked by the nuber of bail outs. The Neighbor's firepower forces the B-ranks into hiding, but following the arrival of Kōhei Izumi, Shun Midorikawa and Yōsuke Yoneya Azuma incites them to fire at will to pressure him into revealing an opening. The non-Attackers act as bait, with Lamvanein targeting Kuruma. However, the Neighbor sees through the trap and turns to shoot at Yoneya, but Kuruma, Midorikawa, Tsuneyuki Okudera and Kotarō Tomoe combine their Shields, allowing the A-rank to close the distance unharmed and to defeat Lamvanein. Yoneya congratulates Kuruma on his show of terror, which however was genuine. Kuruma is subsequently reassigned to the defense of the southern area of Mikado City.

After the end of the invasion, Suzunari First becomes the recipient of an Excellent Distinguished Service award.

B-Rank Rank Battles Arc
On February 5 Suzunari First fights a rank battle against Nasu Unit, Urushima Unit and Kakizaki Unit, which results in Suzunari First's sixth consecutive victory against Nasu Unit. On that same day Murakami spars with Yūma, which he shares with his teammates the following day as they begin to discuss their plans for their upcoming match against Nasu Unit and Tamakoma Second. Kuruma is impressed by the newcomer's score. Kuruma and Murakami agree that it would be better to fight Tamakoma Second's ace together. He then tries to calm Yuka Kon when Taichi Betsuyaku arrives and immediately proceeds to create problems with his clumsiness.

Two days later, on February 8, after the members of Suzunari First review their plans, they wait for Murakami to wake up. Kuruma spawns in the south-eastern area of Riverbank, and after a moment of befuddlement caused by the severity of the weather conditions, he starts moving north. After Kon tags Nasu and Osamu, Kuruma asks for the positions of the fighters on the other bank. He tells Betsuyaku to move east so as to shoot at Yūma should he attempt to cross the river. When the bridge is destroyed, Kuruma suspects Tamakoma Second to be responsible. Kuruma shields Betsuyaku after a reckless pickoff attempt on Nasu and the two join forces to take down the enemy ace, combining their fire and Shields. However, Nasu quickly breaks through their defenses by faking a widespread attack, disabling Kuruma's left arm. The captain of Suzunari First insists on returning fire lest they be defeated before Murakami crosses to the east bank. With Osamu's help they manage to hold out for a while longer, although they continue to be pushed back. Kuruma suggests getting closer to keep Nasu away from the river. As they jump off a building, Betsuyaku sees Nasu's incoming rounds and pushes Kuruma away. The bullets explode on contact, causing the Sniper bails out.

When Murakami is also defeated, Kuruma is left to confront Nasu by himself, the enemy captain becoming more bold after Chika's location becomes known. His right leg is injured, which puts him at an even greated disadvantage against the agile ace. His limited mobility further deteriorates when Chika blows up the levies, flooding the eastern bank. After narrowly surviving Nasu's Tomahawk, Kuruma fires his Hound skyward moments before a second round forces him to bail out. His last ditch effort pays off, however, the homing bullets hitting Nasu from her blind spot and eventually leading to her defeat for excessive trion loss. After the end of the match Kuruma is embarrassed by Betsuyaku's praise, and tells Murakami not to worry about his defeat. He becomes concerned when Kaho Mikami suggests that the strategic skills of the captains are the main factor behind the point spread, which Kei Tachikawa denies, instead chastising Murakami for losing to an opponent he should have been able to best. Kuruma points out that the top Attacker is so tough on Murakami only out of esteem.

At some point after the match Kuruma and Murakami begin to work on a new formation which greatly increases their firepower at mid-range, rapidly making it combat-worthy through a mixture of practice and Murakami's Side Effect.

Kuruma is assigned to the half of close and mid-ranged fighters led by Kōtarō Suwa during Galopoula's blitz. They move forward to intercept the Idras, but the Dogs summoned on the roof by Koskero deprive them of the Snipers' cover and force them to fall back. When Kizaki, Arafune, Shun Midorikawa and Shinnosuke Tsuji repel the Dogs and the Snipers are freed up, the Gunners manage to push back the Idras. They gather briefly to discuss the chain of command, with Kuruma stating that leaders are normally decided by rank or age. With part of the Snipers relocating to the ground level, the close and mid-ranged fighters start to advance as they mow down the Trion Warriors. Kuruma guards the rear of the wedge formation consisting of him and Suwa Unit in one of the most forward positions. Hisato Sasamori saves Kuruma from a sneak attack launched by an unusually powerful Idra at the cost of mild personal injury. With Sasamori and Tsuji facing off against it, the Gunners are free to go back to engaging the other Trion Warriors. Kuruma is awed by the power of Reiji Kizaki's and Kyōsuke Karasuma's personal Triggers as they rapidly whittle down the remaining Idras. After the enemies retreat, Kuruma thanks the Snipers, and, together with the rest of the ground forces, remains inside the security zone for a while.

The members of Suzunari First gather to prepare a strategy on the week before their match against Kageura Unit, Azuma Unit and Tamakoma Second on March 1. Kuruma states that they need a new strategy apart from their latest formation. Betsuyaku shares his proposal to use darkness to their advantage, combining a nighttime setting with a blackout.

Minutes before the match they discover that Tamakoma Second has added a new member. Kuruma considers changing their map choice, but his teammates convince him to select Cityscape D as previously agreed. Kuruma then proceeds to review the strategy one last time before transmission is initiated. Kuruma spawns on the eastern side of the map and, like everyone else, begins moving towards the mall. Upon learning that Hiro Kitazoe has engaged Murakami, Kuruma rushes to his side even though he would prefer to use their plan on anyone but Masato Kageura. The two captains reach their teammates simultaneously, and a firefight breaks out on the sixth floor between the Gunners of each team. The Attackers soon begin trading blows as well, with Murakami also covering for Kuruma. When Kitazoe threatens to overwhelm him, Kuruma switches into a Full Attack stance while Murakami focuses entirely on protecting him, turning the tables on their opponents.

Kageura and Kitazoe 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, Kuruma has Betsuyaku turn off the lights in the mall, only to turn them on again as soon as the opponents activate visual support. Kageura manages to survive the tactic thanks to his Side Effect, but he is still gravely injured. Kitazoe shoots the light fixtures to prevent the opponents from replicating their plan, and shortly after Betsuyaku bails out the two teams resume fighting outside of the restaurant. With Yūma and Hyuse's sudden arrival the three pairs take some distance as they observe each other. Kuruma and Murakami relocate across the atrium to open fire when Kageura Unit and Tamakoma Second will converge, but Hyuse's Escudo forestalls them.

Both Kageura and Kitazoe bail out as a result of the exchange, the point for the former's defeat going to Suzunari First. When Hyuse dispels the barriers, the two teams clash, with Hyuse's "Asteroid" nearly matching Kuruma's Full Attack in power. Suzunari First gains the upper hand as Murakami cuts down Hyuse's Escudo while Kuruma whittles their Shields away, but the tides turn when Hyuse manages to close in on Murakami and cause an Escudo to burst out of Murakami's own body, pushing Kuruma towards a concealed Osamu. The captain of Tamakoma Second manages to wound Kuruma, but fals to defeat him before Yuzuru Ema snipes at him through the ceiling. After the end of the match, Kuruma consoles Betsuyaku, saddened by the fact that his strategy earned the team only one point.