Taichi Betsuyaku/Plot

Background
Betsuyaku was scouted by Border from outside the prefecture on account of his youth, trion amount, and energy, and ended up joining the organization approximately one year before Chika Amatori and Yūma Kuga. Tatsuya Kuruma used to keep an aquarium in the building of Suzunari Branch, but after Betsuyaku accidentally boiled all the tropical fish inside to death no new aquaria were installed. On another occasion Kuruma gifted Betsuyaku a hat out of concern for his clumsiness.

Around eight months before his unit's match against Nasu Unit and Tamakoma Second, Kō Murakami was found crying in a corner by his teammates. When he heard that Tetsuji Arafune quit being an Attacker, Betsuyaku cheerfully exclaimed that it is because of Murakami's talent, worsening his teammate's mood. Later, however, when he hears the full story through Kuruma's video, he is taken aback by how nice Arafune is.

Introduction Arc
Suzunari First presumably takes part 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 successfully dispose of the Trion Warriors, but a Rabbit emerges from a carcass. 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. Betsuyaku and Kuruma split up and the Sniper goes to Azuma's side. A Gate opens right next to them from which Lamvanein emerges. Azuma orders Betsuyaku to fall back, and the two witnesses with horror the humanoid Neighbor's power as he single-handedly obliterates Chano Unit. As they run away, however, Lamvanein rapid-fires at them, causing Betsuyaku to bail out.

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

B-Rank Wars Arc
On February 1, Suwa Squad manages to force all of Suzunari First, including Murakami, to bail out, resulting in the former unit's victory.

Round Two
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.

Round Three
The following day, Betsuyaku arrives at Suzunari Branch while his teammates discuss Murakami's match against Yūma Kuga. Seeing that Kuruma is going to eat instant noodles, Betsuyaku offers to pour the water for him, which leads to a series of mishaps on his part. Kuruma calms him down and proposes to discuss their strategy for the match against Tamakoma Second after he has eaten.

Two days later, on February 8, after the members of Suzunari First review their plans, they wait for Murakami to wake up. Betsuyaku spawns in the south-eastern area of a shockingly stormy Riverbank, the wind tossing him around in his Bagworm. Despite the downpour he manages to spot Osamu Mikumo and Rei Nasu, and hypothesizes that Chika is wearing Bagworm while Akane Hiura is not. Kuruma instructs him to move towards the river so as to shoot Yūma in case he attempts to cross it with Grasshopper. He proclaims that compared to Lamvanein, Nasu is not a threat. Betsuyaku and Kuruma are soon separated from Murakami due to Chika destroying the bridge, which reminds Betsuyaku of Aftokrator's invasion. Soon he attempts to snipe Nasu while she pursues Osamu, but the rain prevents him from aiming properly and he misses. He dismisses the Operator's warning, believing that the weather will prevent Nasu from hitting him as well, but he is quickly forced to run away from her Viper. Only Kuruma's well-timed Shield saves him, prompting the Sniper to reevaluate his assessment of the danger.

Betsuyaku and Kuruma join forces against the captain of Nasu Unit, combining their firepower and Shields. However, Nasu quickly breaks through their defenses by faking a widespread attack. Albeit wounded, Kuruma incites Betsuyaku to return fire lest they are overwhelmed before Murakami reaches them. With Osamu's help they manage to hold out for a while longer, although they continue to be pushed back. As they jump off a building, Betsuyaku notices that Nasu's incoming rounds are slower than before and push Kuruma away. The bullets explode on contact, causing the Sniper to bail out.

After the end of the match, a jubilant Betsuyaku congratulates his captain on taking out Nasu. He listens to the commentators' closing remarks and when it is announced that Tamakoma Second will move to the upper tier of B-rank, he claims that they will so too and hopes that the rival team will lose.

Round Four
During stealth and target acquisition training Hokari is shot by Isami Tōma without being able to retaliate. He finishes the session in 13th place, amusing Yoshito Hanzaki, Shōhei Kodera and Ken Satori with the peculiar distribution of the marks on his face.

Galopoula's Blitz
Since Azuma Unit, Kageura Unit and Yuba Unit fight in the night division of rank battles on February 19, Suzunari First must have competed in the day division against Ninomiya Unit, Ikoma Unit and Ōji Unit. They rank sixth after the end of the match.

That same night Betsuyaku is assigned to the half of Snipers led by Tōma in preparation for Galopoula's incursion. The Snipers are all stationed on the roof of HQ. When they open fire against the approaching Idras, the Trion Warriors counter by combining their shields, causing Betsuyaku to panic, but the Snipers quickly adapt by focusing their fire on each cluster. Koskero retaliates by summoning dozens of Dogs on the roof, driving the Snipers back. Arafune and Reiji Kizaki proceed to fight them back, impressing Betsuyaku. Shortly afterward, while Betsuyaku and Tōma goof around, Shun Midorikawa and Shinnosuke Tsuji arrive to help, so the Snipers are free to resume their positions. Betsuyaku remains on the roof while the Snipers led by Kizaki provide assistance to the agents on the ground. When the enemy is vanquished, Hiura proudly celebrates Nasu defeating an enemy agent, with Betsuyaku claiming to have always known that she was a formidable fighter.

Round Five (Night)
After the results of the night division are tallied, Suzunari Second slides to seventh place.

Round Six
Suzunari First fights against Ninomiya Unit, Kageura Unit, and Azuma Unit in the night division of the sixth round of rank battles. The team ties with Azuma Unit while Kageura Unit and Ninomiya Unit lead with three points. No unit receives the survival bonus due to there being multiple survivors.

Round Seven
The members of Suzunari First gather to prepare a strategy three days 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, although Betsuyaku thinks that they are faring fairly well thanks to it. Kuruma counters that their opponents will soon adapt, so Betsuyaku considers poisoning the opposing Operators. When Kon reminds them that the choice of the map will be theirs, Betsuyaku shares an idea he had been wanting to try for some time: choosing a nighttime setting and then turning the lights on and off inside a building to blind and dazzle their opponents.

Minutes before the match, Kuruma worries about the discovery Tamakoma Second has added a new member, but Betsuyaku is confident that it will not be a problem, as Tamakoma Second has never faced their new formation. Murakami points out that they have probably have seen it in the logs, but a now more concerned Betsuyaku insists on remaining optimistic. Shortly before transmission, Kuruma goes over the strategy one final time, telling Betsuyaku to head straight for his target while Kon helps him with the timing. Kon feels nervous, but Betsuyaku excitedly repeats that it will work. Betsuyaku spawns in an intersection adjacent to the mall and activates Bagworm right away, heading for the building. He narrowly avoids an encounter with Noboru Koarai and resumes crawling towards the power room. When he reaches it, he sets up two Escudo to protect the fuse box and himself and awaits Kuruma's signal to turn off the lights and then to turn them back on, a tactic which results in Kageura taking a massive hit from Murakami. Yuzuru Ema attempts to snipe at the fuse box through the walls, but the barriers Betsuyaku set up protect it. However, he is forced to leave the room when Kon warns him that someone who disappeared from Radar is coming for him. His escape is cut short by Hyuse, who traps him with Escudo and forces him to bail out. The failure of his plan and Sumiharu Inukai's commentary cause him to burst into tears, but his mood improves drastically when Jun Arashiyama praises his unpredictability and its effect on future matches.