Hisato Sasamori/Plot

Background
Sasamori joined Border approximately two years before Yūma Kuga and Chika Amatori. On a single occasion he won 4 times out of 10 against Shun Midorikawa.

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

Large-Scale Invasion Arc
Suwa Unit 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. A Rabbit emerges from the carcass of one of the defeated enemies, its armor withstanding Kōtarō Suwa's and Daichi Tsutsumi's bullets. Sasamori is thus deployed to pierce it, but the Trion Warrior shocks the Attacker on contact, paralyzing him. Before it can abduct him, Suwa draws its attention while Tsutsumi rescues his teammate, only for the captain to be captured instead. Sasamori and Tsutsumi are saved by the arrival of Kazama Unit. Sasamori insists on fighting alongside the A-rank agents, but he reluctantly accepts to withdraw when Sōya Kazama claims that he will only bail out fruitlessly. Tsutsumi and he are dispatched to fight Trion Warriors in other areas. When Kazama Unit manages to kill the Rabbit, they find out that Suwa has been turned into a trion cube. Kazama tasks Tsutsumi and Sasamori with bringing it to HQ for analysis.

After some initial difficulties, the engineers succeed in reverting the cubification in time for Suwa to intercept Enedra as he rampages inside the base. His Black Trigger appears to make him immune to damage, but Kazama observes that his trion body must possess a relay center and a supply system and that Suwa Unit's shotguns are ideal for finding them. Suwa and Sasamori lure Enedra into one of the training rooms. Just as Enedra delivers the killing blow, Tsutsumi activates the simulation mode, preventing Enedra from causing any more damage. Sasamori remarks that as long as the simulation lasts, they will be unable to defeat Enedra as well, to which Suwa replies that their goal is to analyze the enemy's Black Trigger and prevent him from noticing the control panel by the door. Right after Suwa notices a hardened shell inside the Neighbor's trion body, Enedra creates more and launches a gaseous attack that triggers the control panel, ending the simulation. He destroys the room, but before he can finish off his opponents, Shinoda joins forces with them.

The Director single-handedly destroys all of the shells before Suwa Unit can assist him. However, Enedra removes his vitals from the shell at the last moment and paralyzes Shinoda with his gaseous attack. Suwa and Tsutsumi resume firing at him, hitting the shell, and marking it with Starmaker before he can create decoys. Meanwhile, Sasamori activates Chameleon and attempts a sneak attack, but Enedra impales him. This was, however, part of the plan, as the destruction of Sasamori's trion body creates a smokescreen that conceals Shirō Kikuchihara's and Ryō Utagawa's own reappearance, allowing them to deal the finishing blow. Sasamori is moved by Kazama's praise.

After the end of the invasion Suwa Unit is the recipient of an Excellent Distinguished Service award.

B-Rank Rank Battles Arc
On February 1, Sasamori bails out in a rank battle against Suzunari First, his obstruction allowing Suwa and Tsutsumi to overwhelm the powerful Kō Murakami with their combined firepower.

Round Two
The following day, three days before their match against Tamakoma Second and Arafune Unit, the members of Suwa Unit gather to prepare a strategy in HQ's cafeteria. Sasamori shows his teammates the footage of Tamakoma Second's first rank battle. Suwa asks him about his track record against Midorikawa, and his answer prompts him to decide that Sasamori will hold Yūma down while he and Tsutsumi blast both of them away.

On February 5, when Tamakoma Second's map of choice is revealed to be Cityscape C, all of Suwa Unit is taken aback, with Sasamori wondering if their opponents are not afraid of getting sniped. The members of Suwa Unit convene to start the match by regrouping and then charge up the hill.

Sasamori spawns to the far east of the map. Fearful that Arafune Unit will gain the high ground first, he hurries to meet up with his teammates. As he is about to cross a street, he is grabbed by the collar by his captain, who narrowly saves him from a lethal shot by Atsushi Hokari. The three are pinned in place until Tamakoma Second draws Arafune Unit's attention. When Suwa loses a leg while pursuing Tetsuji Arafune, Sasamori hurries to his side and asks if they should fall back, but the captain insists on pressuring the Snipers. He then sends Sasamori after Hokari as they both activate Bagworm. Hokari spots the Attacker and begins to flee, attempting to rattle him by attacking his confidence. Realizing that he has run out of options, Hokari stops in his tracks to shoot at Yūma, allowing Sasamori to cut him down.

The Attacker then activates Chameleon and approaches Yūma. Contrary to the latter's expectations, he restrains him while remaining invisible. The ace of Tamakoma Second stabs him, but does not manage to deal lethal damage before Suwa can get into position to pepper both of them with bullets. Just then Chika demolishes the houses they are standing on, allowing her teammate to free himself and force Sasamori to bail out. As a result of the match, Suwa Unit drops to 10th place.

Round Four
On February 8 Sasamori, Suwa, and Mitsuru Tokieda walk through the base together when Yūma spots them. He walks over and Suwa and he starts horsing around, to Sasamori's amusement.

Galopoula's Blitz
On the night of February 19 Sasamori is assigned to the half of close and mid-ranged fighters led by Suwa during Galopoula's incursion. 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 Reiji Kizaki, Arafune, Midorikawa and Shinnosuke Tsuji repel the Dogs and the Snipers are freed up, the ground troops manage to push back the Idras. 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.

Tsutsumi takes the center of the wedge formation consisting of him, Suwa, Tsutsumi and Tatsuya Kuruma in one of the most forward positions. Suddenly, they are targeted by an unusually powerful Idra. Sasamori manages to foil the flanking attempt, although he is injured in the process. After failing to hit the exceptional Trion Warrior, Suwa sends Sasamori after it, with Tsuji backing him up. He impresses the higher-ranking Attacker with his calm analysis. After the enemies retreat, Sasamori, together with Tsuji, Futaba Kuroe and Ai Kitora, are praised by Jun Arashiyama for holding back the enemy ace. Having been wounded, Sasamori presumably returns to the base, as per Shinoda's orders, while the rest of the ground forces lingers in the security zone a while longer.

Round Seven
Sasamori roams the solo battles hall with Noboru Koarai during the next enlistment day. The two take notice of the trainees' excited chatter and ask Yūta Miura and Kotarō Tomoe what is happening. To their befuddlement, they learn that Hyuse went from C-rank to official agent in only a few hours. The four agents propose to fight a five-round solo battle against him each and Sasamori goes fourth. Having studied Hyuse's moves during the other three matches, he manages to score one win. He then follows his duels first against Tatsuhito Ikoma and then Kei Tachikawa with interest, and joins the other B-rank agents in congratulating Hyuse.