Kei learns about the existence of immortal beings, Ajin, as well as their discovery 17 years ago in Africa. Later, he is hit by a truck, is killed, and lives.
Tropes:
- Cliffhanger: The episode ends with Kei and Kai on the run as the police, the government, and the entire public hunt Kei down. It also ends with "To Be Continued".
- Dynamic Entry: Kai saves Kei from police capture by appearing out of nowhere and knocking out the policeman with a Diving Kick.
- Establishing Series Moment: AJIN: Demi-Human Season 1 starts with a battle scene where African gunmen are being outgunned by a sole, nigh-unkillable soldier. This soldier is dubbed a "Soldier of God". Even a rocket launcher can't stop him. Then, the P.O.V. character shoots the soldier in the back. Just as he thinks he did it, the soldier gets back up, wounds healed, and prepares to finish him off. But then the "Soldier of God" is unceremoniously felled by a couple of tranquillizers and put in a bag by the US military, eyes wide open. It becomes clear that this work has a gritty tone, is about immortal beings like that soldier (called Ajin), and hints at how said beings, for all their immortality, are vulnerable, hunted, and treated like animals.
- Irony: Kei distances himself from his former delinquent friend Kai (even calling him a freak towards his peers) to become an upstanding member of society. After his nature as an Ajin is exposed, Kei is on the run while society turns on him. Guess who's the person he reaches out to (and later bails him out).
- R-Rated Opening: The first shot of this anime is an African man lighting up his cigarette. Then, a gun battle happens, with real bullets and automatic rifles. That's seinen for you. Not for kids.
- Rule of Three: Kei, The Protagonist, is the 3rd Ajin discovered in Japan. This revelation is what kicks off the plot.
- Super-Scream: Kei screeches in panic as his status as an Ajin is laid bare in front of the bystanders and students around him. They're immobilized by his scream. It turns out this is an innate Ajin ability, of which he is unaware.
- Tempting Fate: As Kei and his peers joke about Kai possibly being an Ajin in disguise (because he's "different"), Kei asks, "What's that stuff have to do with us?" He then gets exposed as an Ajin after getting crashed by a truck and lives.
- Title Drop: Kei speaks of the title of the episode, "What's that stuff have to do with us?", while conversing with his peers about Kai possibly being an Ajin. It shows how Kei sees the Ajin issue as insignificant. Until he gets involved after coming back to life in a traffic accident.
- This Cannot Be!: Non-villain example. Kei expresses disbelief after he comes back to life from a traffic accident, his nature as an Ajin revealed to the public. He shouts, "I'm not", "This is some kind of mistake", and the like.
