The Shinya Nakamura Incident (中村慎也事件 Nakamura Shinya Jiken) is an interlude chapter of the manga Ajin: Demi-Human, created by Gamon Sakurai.
The chapter starts off with the titular character of the chapter, Shinya Nakamura, standing in shock as he stares at his own cut off hand from a motor accident. Nakamura realizes that his arm is regenerating and soon comes to the conclusion that he is also an Ajin - a "monster", as he said, that is unable to die. He quickly tries to calm himself down as he realizes that nobody was a witness to the incident. As he struggles to keep his humanity whilst hiding the evidence, he panics when he sees a Black Ghost behind him. He manages to remain calm when the Ghost disappears and go back to what we can assume is his apartment, with only a few people giving him weird looks, but otherwise went unnoticed.
Nakamura is later seen at his home, brooding. He opens up his laptop and researches more about Ajin. He is relieved as he remembers that there are not a lot of Ajin in the world, and that the chances of him being discovered are slim as long as there isn't any crucial evidence to point otherwise. He finds out that Ajin were discovered in the 1990's and that there are 45 discovered around the world thus far. The webpage also said that "research on them is still underway". He also finds out that despite from their immortality, Ajin are no different from humans. Once the public realized that they weren't dangerous, the panic subsided, and Ajin came to be viewed as valuable research subjects for the sake of human evolution. It is said that a movement started where groups would capture Ajin and sell them to other countries, black markets, and so on. This became known as "Ajin hunting". Shinya then thinks that this is what will happen if he gets caught.
He then imagines himself strapped to a chair, completely naked, while being about to get brutally tortured. He panics that he'll be an experimental animal forever, forever unable to die. He has to remind himself that other than death, there is no way of identifying someone as an Ajin. He reasons that he hid the evidence and that he made it look like his bike was illegally dumped and the blood got washed away by the rain. However, he still wondered what to do with his left over arm. He states that it's the only remaining evidence that he is an Ajin. As soon as he thinks this, he hears a knock on the door. He quickly wraps the arm around a newspaper. From behind the door, someone shouts his name and asks him if he's there. Shinya identifies the person as Yūsuke and calms down.
He opens the door and Yūsuke tells him that he heard that he took the day off from University because of a cold. He is holding a bag of groceries and tells Shinya that he bought him pudding, and asks him if he's surprised. Shinya laughs and tells him that he's not. He then tells Yūsuke that he is still feeling a bit off and it would be better if he went home because he would feel bad if he caught his cold.
Yūsuke stares at him with concern and asks Shinya why he is suddenly crying. Shinya didn't realize he was crying and is confused when Yūsuke hand him over tissues. He tells him it's nothing, however, Yūsuke doesn't believe him and insists that something must have happened. He asks him just how many years he has been his friend and Shinya looks at him with shock. As he is about to confess that he is an Ajin, he reminds himself of the consequences that this might carry and quickly rejects the confession. He apologizes and tells Yūsuke again to go home. Yūsuke is deeply saddened by this, however, he complies with his friend's wishes and leaves.
Some time later, Shinya is seen walking along a road to dispose of his right arm. As he's crossing the road, he encounters a Black Ghost and wonders what that thing is. The Ghost mimics his words from earlier - "I'm okay" and "as long as I hide" and Shinya is left traumatized with fear. He thinks he is going crazy and starts running away, asking someone to save him. As he runs, he is almost hit by an upcoming car if somebody hadn't grabbed his hand. It turned out to be Yūsuke, who later asks him if he's okay. Shinya then realizes that if it's him, he wouldn't mind being sold out because otherwise his heart won't hold out. As he is about to tell him that he's an Ajin, a group of people approach them who seemingly know Shinya. Shinya realizes that he was exposed but tries to figure out how, as he is carrying the evidence. One of the men from the group then take out a helmet, and Shinya panics but remembers that his face was uninjured. The man tells him that forgetting something like that only proves that he is a monster. He exposes his helmet to him, which contained Shinya's decapitated head.
Shinya screams in agony as he realizes his mistake, while Yūsuke looks shocked. The man then introduces himself as Kido from the Ajin management committee. He says that in accordance with special measures concerning Ajin, they will be taking Nakamura into custody.
Shinya then thinks that this was a problem even before he became a "monster" - that he hasn't been himself for a very long time. He cries as he realizes this and thinks to himself that he did something very bad to Yūsuke by making him involved in all of this. As he's reduced to tears, Kido points his gun at him, saying that stopping their movements by killing them is the basic method of capturing Ajin. However, as he is about to shoot, Yūsuke covers Shinya with his own body, protecting him from the shot. Shinya is horrified as he holds Yūsuke's face while he dies. He then notices a shadow coming out of Yūsuke body and realizes that it's the Black Ghost again. The Ghost tells him to run and he is angered for what they did to Yūsuke. As he gets up, he gets shot in the head several times and he collapses to the ground. Kido tells the other men to restrain him before he regenerates. However, one of the men is impaled by the Black Ghost's claws and the other men stare in shock. They turn around only to find dozens of other Black Ghosts surrounding them.
The Black Ghost says that they'll kill them and proceeds to rip the men to shreds while Kido attempts to shoot them. Shinya then manages to revive and apologizes to Yūsuke, but thanks him for what he did. The remains of the Black Ghost tells him to run, as before, and Shinya complies.
The scene cuts to Tosaki talking to a the cabinet minister about the incident. The cabinet minister tells him to investigate what happened, and to prepare any counter measures if necessary. Tosaki agrees and is seen later walking along a corridor, annoyed. He thinks that having an Ajin on their side would make his job much easier. He then remembers that in Hyogo, there was an 'unconfirmed Ajin' that's about to die. He goes there to see if he's correct.
The next scene is of Shinya again, walking on a street with his face concealed. He checks the newspaper and is notices that his name and faces have not been published. He thinks that it is most likely due to the fact that they're afraid he'll summon the Black Ghosts again. He then orders a taxi and asks him to take him to the station. He also tells the driver to drive safely, because we only live once, after all.