Arata Ookoba/History

Episode 5
Through the Drive-In tori television commercial and coverage of Kashima Gatalympics, he realized that Junko had some familiarity and began his investigation.

Episode 6
In episode 6, after something strange about Franchouchou happened, his photographer and he started investigating Franchouchou's official website. Later in the episode, they are seen at the closed concert and notice the strange attitude of Junko and Ai.

Episode 7
At the Saga rock event, he attended to take photos of the participants and in his research, it was seen that he recognized Ai

Episode 8
In the episode of Lily, they are seen behind Franchouchou for a few moments before Takeo arrived.

Episode 12
In the last episode, it is seen that he has something behind. After Arpino concert, he compares the photos of Junko, Ai, and Lily. Junko's photo looks more worn than the others, so it is to be assumed that it had been stored for a long time.

Episode 14
Inubashiri tells him that Franchouchou has returned to being an idol group, and he replies that he saw it on their ugly website. They are both shocked to hear on the radio that #2 is on the radio with White Ryu and that Franchouchou will be taking over as the new radio hosts in Saga, causing Ookoba to spit his curry on Inubashiri.

Episode 15
Another cameo, this time watching No. 3's solo performance on his office television. Later, he asks Inuhashi about Franchouchou's upcoming performance and doubts that the group will manage to surpass Iron Frill at the Saga Arena.

Episode 16
Cameo without speaking in the Saga Arena.

Episode 18
Despite continuing to investigate, he has not been able to get anything conclusive from the girls. Inubashiri mentions that people on the internet are noticing more similarities with number 3, number 4, and number 6, but that most people only think that they are doubles of the already deceased girls. He also annoys Ookoba by telling him that those girls have revived as zombies. A phrase that will be relevant later.

Passing through one of the streets of Saga, he runs into number 0 and decides to follow her secretly while taking a photo of their actions. Something that he notices is that the inhabitants of Saga are very friendly to number 0 and even offer her their food. When passing through a cemetery, he is almost discovered by Tae and Romero, but manages to hide. When they leave, he sees the tomb of the Yamada family and the Minamoto family.

At the mall where Maria works, he is surprised to see number 0 biting Tae, thinking that she is attacking her. When going to plaza 656 he is attacked by Romero when he tried to take a photo of Tae turning her head. Later, he follows Maria's group to the Karatsu boat race, where he emphasizes how bad the Saga police are and tries to take another photo of Tae, but he begins to think that he is just tired of seeing things where there are none.

At the end of the day, he follows Tae and Maria to the girls' mansion and when he is about to leave he decides to turn around and accidentally sees the zombie incident, managing to capture it on camera, and now he does believe that they are real zombies.

Episode 19
Sometime after his discovery, Ookoba manages to find information and news about the deaths of every member of Franchouchou, including Tae. But he did not manage to find any information about Number 5, Yugiri. But despite this, he concludes that everyone in the group is dead.

Episode 22
After discovering the identity of 6 out of 7 girls from Franchouchou, Arata confronts Kotaro in the EFS about the true identity of the Franchouchou girls. Kotaro remains silent about it and makes Arata angry because he thinks Kotaro is using dead girls for exploitation. Arata threatens Kotaro to reveal the article soon so his plan to do the revenge concert doesn't go ahead. At night, and with the article ready, Arata prepares to send it, but suddenly Karatsu's light goes out, and he can't send the article.

Episode 23
Arata is incommunicado due to internet and power failures throughout Saga prefecture, and attempts to call Inubashiri unsuccessfully. In the makeshift shelter, he meets the Franchouchou girls and decides to follow them to see what they do, to which Arata realizes that they are not being controlled by someone. He goes to see them in the area above the shopping center and discovers their true zombie form and is visibly concerned with how they will perform without the proper makeup. When their masks are broken, he is visibly scared, but luckily for the girls, the locals think it's some kind of makeup to entertain children. Kotaro arrives after Arata realized that Franchouchou does this out of love for Saga and that they are girls who operate independently.

Episode 24
Kotaro's favor to Arata was to promote Franchouchou's benefit concert throughout Japan to have more crowds and save Saga. Arata wishes Kotaro that God is on his side, to which Kotaro replies that he doesn't want to involve God at this point. On the morning of the concert and thanks to Arata, Franchouchou manages to fill the stadium thanks to all the sponsors Ookoba got and the relevant people who showed up throughout the season. Arata Ookoba/Historia