Tetsu Totsumura

Tetsu Totsumura (凸村 哲, Totsumura Tetsu) is a police officer who works at the police station on Hitogashima. He is so lighthearted that it is hard to believe that he is a police officer.

Appearance
Tetsu is an adult man with messy orange hair. He is usually in his police uniform and wears yellow glass sunglasses.

1st Loop
The evening of Ushio's funeral, Tetsu sees Mio standing in front of her house and looking inside.

The next day, he misses breakfast and goes at lunch at Kofune's dinner and orders the usual. Mio takes his order and wonder why he didn't came in the morning and Tetsu explains that the whole Kobayakawa family is gone, making him believe that they had a debt and ran in the middle of the night.

2nd Loop
On the second time Shinpei arrived on Hitogashima, he goes outside to take some fresh air. There he sees when Tetsu found Mio staring at her house. Tetsu wonders what is she doing, but Mio then kills him with a kitchen knife. She then produces a shadow, which copies Tetsu's appearance and takes on his identity. Mio wants Tetsu's gun, making the Shadow realize, she has not yet killed the real Mio.

3rd Loop
On the third time, in the evening, Shinpei calls Tetsu and reports a fake fight. As Tetsu goes to check out the fight, he avoids meeting Shadow Mio. The next day, Tetsu gets called to investigate the missing Kobayakawa family. He later goes to Kofune's Diner and sees Shinpei, ready to scold him for the fake fight report, but Shinpei asks him if he wants the usual and Tetsu confirms. Tetsu reveals the Kobayakawa family is gone and that a detective will be coming from mainland this evening. He then gives to Shinpei a phone that Ushio had left him and told him to give to Shinpei if something where to happen to her, a day before she died.

4th Loop
Tetsu is on his way to the bar to drink and talk with Erika, but encounters Mio, who wonders if he saw Shiori, but he denies it. The two then see Shiori pointing at a manhole, which is slightly opened. Tetsu doesn't want to go there as he will stink and Erika won't like him, but Mio states that if he finds the missing girl, he will be a hero and girls will be all over him. That convinces Tetsu, who then leads them into the sewers. Following the sewers, Tetsu starts to complain, but Mio tells him he will tell Erika how brave he is, so he decides to continue. They reach a dead end, but Shiori flashes and eats the iron bars, allowing them to proceed.

Tetsu finds badly injured Ryunosuke who switches to Hizuru, who asks where is Mio. Tetsu reveals that a monster showed up and took her. She wonders about his gun, but he guesses he dropped it. He tried to shoot the baby monsters, but tripped and fell, and then ran. Hizuru states he made the right choice. She asks him to carry her, deeper into the cave. As he takes her, she shoots at the shadow parent and frees, Shinpei, but then gets killed by it. The shadow then shoots and kills Tetsu.

6th Loop
Tetsu along Shinpei's friends is called to the elementary school. There Ushio shows them her memory of the previous loops. Shinpei asks them to help him and fight the shadows. Tetsu find it crazy and suicide, but as the rest agree, he agrees too.

8th Loop
Hizuru receives a call from Shinpei, telling her that Ushio is dead and wants them to regroup at Torajima. Reaching Torajima, Hizuru's group is suspicious as if Ushio is dead, so could be Shinpei and this can be Haine's trap. Hizuru tells Ginjiro to stay at the sniper position, but he tells her he can only cover southern part of the island. Hizuru explains that if Shinpei is a shadow, she will lure him there and Tokiko can use the shadows to strike. Looking at Tetsu, she wonder why is he even there, but hands him a gun and tells him to do his best to survive. Later Hizuru gives a signal and they assist her, but as things turn bad, Ginjiro and Tetsu help Tokiko escape.

9th Loop
Shinpei arrives at Torajima, witnessing Shide defeating one of Tokiko's stray shadows and also the defeated Hizuru. Shide explains that thanks to Shinpei restarting the loop, he could fight Hizuru again and knowing what she would do, made the fight easy. Haine then retreats with Shide and the group witness the final moments of Hizuru.

Etymology

 * The name Tetsu means "philosophy" (哲).
 * Tetsu's surname Totsumura means "convex, beetle brow, uneven" (凸) (totsu) and "town, village" (村) (mura).