Shinpei Ajiro

Shinpei Ajiro (網代 慎平, Ajiro Shinpei) is a 17-year-old boy who returned to his hometown of Hitogashima for the first time in two years to attend the funeral of his childhood friend, Ushio Kofune. Since he lost his parents at an early age and grew up in the Kobune family, he has been close to Ushio and Mio as if they were his family. He has a habit of trying to "look down" on his situation objectively.

Appearance
Shinpei is a young man with medium long black hair and blue eyes. He usually wears a white shirt and blue shorts.

Plot
After two years away, Shinpei returns to Hitogashima to attend his childhood friend Ushio's funeral. On the boat, he dreams of she asking him to find her and protect Mio. Stepping on the island, Mio welcomes him and they head towards the funeral while chatting about various subjects. At the funeral, his friend Sou explains that Ushio saved a kid, Shiori Kobayakawa, from drowning, but drowned herself. That evening, Sou calls Shinpei and explains that the rumour about his father performing an autopsy on Ushio isn't real, but they did find strangler marks on Ushio's neck. However, as there was no one around suspicious at her death, they labelled it as incident.

The next day, Shinpei helps out at Kofune's dinner. A drunk man, Nakamura asks him if he found the woman with glasses he was looking for, but Shinpei thinks he confused him for someone else. The police officer, Tetsu comes and explains that the whole Kobayakawa family had vanished. Hearing that, Mio runs away and Shinpei follows her. After catching up to her, Mio explains that Shiori said she saw a girl looking like her about a week before the incident. An old hunter, Ginjiro Nezu, tells them that's a shadow and those afflicted by shadow sickness, see their shadow and then get killed by it. The shadow then acts as the killed person and kills the remaining family. It used to be quite common sickness before the war and those afflicted went to Hito shrine for cleansing. Mio then states she saw Ushio's shadow along with Ushio, three days before Ushio died. Shinpei then decide they go to the shrine to learn more about the shadows. However, the shrine is closed at the moment and Mio sees Shiori in the forest and they run after her. They are unable to find Shiori, but hear a gunshot and following the sound, they see the woman with glasses bleeding from a gunshot. Mio heads to get help and the woman tries to tell Shinpei something, but get shot in the head. Shinpei then sees Mio holding a gun and holding the Mio that was with him as hostage. The other Mio then shoots Mio and Shinpei. Shinpei then awakens back at the boat where he met the woman with the glasses.

Shinpei realizes his day is repeating and notices Mio's bike had a cut break wire. That night after preparing dinner, he goes out for a fresh air, thinking if someone tried to kill Mio. He ends up seeing Tetsu who sees Mio standing in front of the house. Mio then kills him with a kitchen knife and creates a shadow that transforms into Tetsu, making Shinpei realize she is a Shadow too. She takes Tetsu's gun and explains she wasn't able to kill Mio yet. However, Sou calls Shinpei, which reveals him and Mio kills him. She starts to explain why she can't make a copy of him, but Shinpei dies before he can hear the rest. Shinpei then finds himself travelling somehow and awakening on July 22nd as he steps on Hitogashima.

This time, Shinpei tries to stop Mio from falling in the water, but ends up falling himself and Mio jumps in to help him out. After reliving the same day, that evening, he calls Tetsu reporting a fake fight in order to keep him away from Shadow Mio. He sets up his phone outside the house and has it recording. In the morning, he shows the footage to Mio, explaining that on the video she can see a Shadow, that is there to kill Mio. Shinpei reveals he knows that Ushio saw her Shadow too and Mio then guesses that the Shadow may have killed Ushio.

Etymology

 * The name Shinpei means "prudent, careful" (慎) (shin) and "flat, broad, level, even, peaceful" (平) (hei/pei).
 * Shinpei's surname Ajiro means "network/net" (網) (a) and "generation" (代) (shiro/jiro).