Hiroki Nagase

Hiroki Nagase (長瀬 裕樹) is a 17-year-old high school student and the team leader of the Team X.

Character History
Nagase and his friends found Chihiro wandering the streets after he had escaped from 4C. They took him into their care, and convinced bar owner Makoto Shido, former leader of the Nozama Peston Service, to allow him to stay at his bar. Sometime later, the gang would discover the existence of Amazons, as well as Chihiro being able to sense them and fight them. Upon learning this, Nagase and the others form "Team Kiss," a group who hunts down Amazons and posts the fights online. As a result, they receive great popularity and cash.

After a hunt and returning to Shido's bar, Nagase gets into a fight with Chihiro after they compare him to an Amazon if only jokingly. Before things can escalate, Shido arrives and told them to knock it off. The next day, Chihiro senses another Amazon at a chapel, starting another hunt for them. After Chihiro is overwhelmed, Nagase finds Iyu approaching, expressing shock upon seeing her, as well as her turning into an Amazon. After the Amazon is killed, Nagase learns that Chihiro had apparently felt a desire to eat humans, but held no such desire towards Iyu. More Amazons then arrived, and were quickly dispatched. A member of Team Kurosaki, Fudamori, then fries one of the phones of Narase's friend to prevent them from further recording.

When they return to the bar, they worry about Chihiro after he was taken back to 4C. Nagase reveals that he has seen Iyu before - she was his classmate, but was announced dead alongside her whole family due to an Amazon attack. Later, the news reports 4C's findings about the New Amazon Cells being inside water tanks provided by a company, though the news refers to it as a harmful mold. Takumi notices this, and shortly afterwards, becomes an Amazon while proceeding to eat one of his friend's legs, and is later taken down by Shido. Nagase's friend is rushed to the hospital, but dies from blood loss. Nagase expresses horror that Takumi never revealed that he was an Amazon, but Shido told him that he wasn't an Amazon, but became one instead. After hearing about the tainted water supply, Shido leaves and told Nagase not to come back to his club.

Later, Nagase comes to Shido's bar, demanding answers. With the arrival of Misaki and Nozomi, Shido reveals to Nagase that five years ago, he and his friends hunted the original Amazons that appeared, and is about to start again. Nagase requests to join them in order to avenge his friends. While the others are reluctant, Shido allows him saying its better to have him be with them than act on his own.

The remains of Nozama Peston Services then head out with Nagase in tow. He learns from Misaki that the source of the infection is a tainted water source, much to his surprise. Shortly after they arrive, they are set upon by Amazons. Nagase is unable to help them at all, but watches in awe as they deal with the Amazons and tries to help, only to get in the way. After they manage to clear out the area, they then encounter Fukuda, who was also tasked by 4C to investigate a tainted water supply. Nagase then meets Mamoru, a former member of Nozama Peston Services, as well as their resident, who is also responsible behind the tainted water supply as part of his "revenge" against humans for hunting them.

The Nozama Peston Service members are reluctant to fight Mamoru at first, and Nagase finds himself pinned down when an Amazon tries to eat him, only to be confused when it is unable to. Nagase then learns that the Amazons that Mamoru has been leading are all unable to eat humans, even Mamoru himself, who five years ago ate Misaki's arm and hasn't been able to eat ever since. Mamoru shows disdain for humans who have been hunting them all this time, even though they wanted nothing to do with them. Nagase, in rage, tries to attack Mamoru, but is subdued and has his shoulder dislocated. When Mamoru and the Amazons try to lead, he shouts at Shido to shoot them, but doesn't.

Sometime later after the Amazon hunters return to the bar, Nagase leaves in order to try and clear his head. By chance, he runs into Chihiro, and shows his concern since he has not seen him in a while. The two catch up and Nagase informs him that Takumi had turned into an Amazon and killed Kenta, much to Chihiro's sadness. Nagase then asks about Iyu, with Chihiro asking about her. Nagase reveals to Chihiro that Iyu was his classmate, who always seemed to smile and make cake for her friends. Nagase also learns form Chihiro that Iyu had indeed died due to her father becoming an Amazon, and was made into one herself, albeit as a corpse with almost no will of its own. When Chihiro leaves, Nagase thinks back to what Mamoru said, showing remorse before claiming that humans hunting Amazons is how it should be.

Later, Nagase ponders on his situation outside a shopping center, since he is unable to hunt Amazons by himself. Two students from his school recognize him and ask him when he will be uploading videos again before asking when he intends to return to school, informing that his teachers are losing patience with him. While riding his bike, he finds Iyu, much to his surprise. When he asks her what she is doing, she states that she wants to go to someplace "fun." Humoring her, he takes her to the apartment complex where she once lived. Upon seeing it, Iyu begins to sing, though it attracts the attention of the tenants of the complex, who seem to recognize her. Worried about the complications, Nagase takes her elsewhere.

Their next stop is a zoo that they once went to on a school field trip, though Nagase doesn't recognize it at first, noting that it is closed down. Iyu, surprisingly, remembers it perfectly. While they enter it, Nagase remembers what Chihiro told him and asks if she is truly dead. After some small talk, he asks her to join Team Kiss, claiming that it would be fun while also trying to awaken Iyu's "human" side. Iyu seemingly agrees to this, much to his joy, though he is surprised to learn that there are three Amazons in the zoo, which Iyu combats. He tries to help her, but is unable to properly fend them off. Thankfully, Chihiro arrives, but is surprised to see him with Iyu before transforming, though his performance is lowered due to having suffered a dose of the Scattershot bullet's power being injected into him earlier.

However, they are saved by the appearance of a man carrying a belt similar to Chihiro's, who Kurosaki calls "Jin Takayama." Much to the surprise of Nagase, he transforms right before his eyes, and brutally murders the Amazons. Nagase is shocked even further when Chihiro calls him "Dad" when Jin tells him that he has been looking for him. Kurosaki then notes that Jin is actually blind, though he claims it hasn't affected him much. Nagase is horrified when Jin tells Chihiro that he has come to kill him. Jin then asks Chihiro what happened to his mother, Nanaha. Team Amatsuki arrives in time to evacuate them. As they leave, Chihiro asks Nagase why he was with Iyu, answering that she said she wanted to go someplace "fun."

Upon returning to 4C, Nagase is rudely thrown out, and is denied to join when he asks. However, after Chihiro's berserker rage causes a commotion, he sneaks in, and is utterly horrified when he sees the results. He then finds Chihiro unconscious, though before he can ask what happened, Chihiro flees, screaming in horror. Nagase then learns that the destruction was caused by Chihiro, and Kurosaki orders Iyu to hunt him, horrifying Nagase.

Worried about his friend, Nagase trails Team Kurosaki when they go off to hunt Chihiro, and stops Iyu from trying to kill him, telling Chihiro to escape. He continued to trail after them, and when they take a short break from their search, he pulls Iyu away to try and convince her to not kill Chihiro, giving her the photograph that Chihiro placed on the wall, telling her that he never smiled like that when he was with him and his friends before he says how screwed up this whole situation is. However, he is then pulled aside by Kurosaki, who tells him that Chihiro will eat someone if he continues to interfere. He then tells Iyu that she has "trash" on her hand, which she crumples and tosses to the ground before taking her leave, depressing him further.

He then returns to Shido's bar when he hears someone inside. Thinking its the owner, he apologizes for his intrusion before realizing that its Chihiro, who is gathering the protein food packs. He asks if that was what he came back for. Chihiro states that its the only thing he can eat since he's so hungry, expressing his fear of eating someone. Nagase then asks if he is the point of origin, which Chihiro confirms, even blaming himself for the events that have transpired thus far; Kenta and Takumi's deaths, Iyu dying at her father's hands and becoming an Amazon, yet he wants to live and be with her. Just then, Jin stumbles into the club. He asks if Chihiro killed his mother, much to Nagase's surprise, though Jin claims that it was his own fault rather than his son's. When Jin attempts to kill Chihiro, he knocks down a gun case with a shotgun.

Just as Jin is about to deliver the final blow to Chihiro, Nagase shoots him point blank in the head, telling Chihiro to run. Nagase then aims the shotgun at Jin, asking him if he is truly his father if he's trying to kill him. Angered by his interference, Jin puts him into a chokehold, proceeding to knock him out, though he agrees with Nagase's unfinished statement that he's a "piece of shit."

The Last Hunt
After regaining consciousness, Nagase searches for Chihiro but cannot find him, leading him to call him. After expressing his worry, Nagase asks where he has been. Chihiro then informs him that Iyu had saved him from Jin, and even asked if his wounds hurt, surprising Nagase and asking if she's returning to normal. He grows concerned when Chihiro doesn't answer after a while, and heads to the chapel where they are hiding. When he arrives, he discovers several 4C operatives dead, the room in utter disarray, and Chihiro holding Iyu, crying and asking why no one would leave them alone. Nagase, learning that the armlet is slowly killing Iyu, becomes angry at Kurosaki, claiming that she was close to going back to normal, though he brushes him off. When Chihiro leaves to 4C in order to try and convince Tachibana to stop the armlet, he recalls what Chihiro said earler, sadly wondering if anyone could answer that.

Worried about Chihiro, he heads to 4C and finds him battling both 4C and Haruka, trying to keep Iyu out of the crossfire. However, when the armlet causes more damage to her than she can handle and falls to the ground, his shout causes Chihiro to become distracted and gets wounded, and is soon fired upon when he reverts back to his civilian form. Iyu, seeing this, tries to help him and is attacked as well, which leads Chihiro to try and protect her. When 4C stops, feeling sorry for the two Amazons, which allows them to flee while Nagase prevents Kurosaki from trying to kill them.

After Chihiro and Iyu's death, he returns to his school life, looking at his phone, which has a picture of the two out on their "date" back at the park.

Personality
When first introduced, Nagase comes off as rude and brash, holding resentment towards his parents and dissatisfaction with his current school life. However, upon meeting Chihiro and discovering the existence of Amazons, he grew to love the thrill of danger, excited over something completely different than his boring life. That said, he was hardly a good person, as he held a strained relationship with Chihiro in spite of the fact that he accepted the boy into his life. He often quarreled with him and was easily offended, though he was unaware that Chihiro's reluctance to be near him was because of his desire to eat human flesh.

After encountering Team Kurosaki and witnessing his friend turning into an Amazon and eating one of his friends, Nagase becomes more somber and fully aware of the danger he was throwing himself into. He also developed a hate for Amazons after the event, joining the remnants of Nozama Peston Services to get revenge. However, this seems to waver a bit when he learns that Mamoru, a former member of Shido's group and an Amazon, that his kind have been hunted relentlessly for five years despite not wanting anything more to do with humans, and even virtually unable to eat humans anymore as he learns firsthand, and for a moment grows remorseful.

Nagase has also developed a more friendlier and caring relationship with Chihiro following their next encounter after the latter joins 4C. He showed concern for his friend due to his long absence, even stating that he was worried about him. Furthermore, despite seeing the horrible carnage caused by Chihiro after his transformation and rampage as Amazon Origin, Nagase doesn't see him as an Amazon and tries to help him, interfering with both Jin Takayama and Team Kurosaki's attempts to kill Chihiro. He even goes so far as to shoot Jin in the head when he was nearly about to kill his own son, showing even willingness to kill someone if it meant protecting his friend. Additionally, this action came after he learned that Chihiro was the point of origin behind the Amazon infections, and therefore the indirect cause behind the deaths of his friends, much less the events that have transpired thus far in the season, displaying that, in spite of his hate for Amazons, he does not consider Chihiro one. As the season nears its end, he becomes more and more saddened by Chihiro being hunted by others, and in spite of his attempts to save him and help him, he is killed by Haruka and Jin.

Like Chihiro, Nagase also tries to awaken Iyu's "humanity." At first, he is confused when he sees her for the first time, having heard that she had died, and shows even greater confusion upon learning that she is a literal walking corpse, though his meeting with her while she tries to go to someplace "fun" helps him form a bond with her, enough so that he offers her a place at Team Kiss, saying that it would be fun while also hoping that it would help her awaken her "human" side. He also tries to convince her not to kill Chihiro, which may have served as a possible catalyst to her reawakening her humanity and subsequent action in protecting Chihiro from Jin.

At the end of the series, despite returning to the life he once considered boring, Nagase remembers the adventures he had with Chihiro and his interactions with Iyu, keeping one of the photographs that Chihiro took with Iyu on their "date" as remembrance for them.

Portrayal
Hiroki Nagase is portrayed by Eiji Akaso (赤楚 衛二), who would later go on to play Ryuga Banjou/Kamen Rider Cross-Z in Kamen Rider Build five months later.