The Anachronism Stew and "Groundhog Day" Loop nature of hololive ERROR obscures the flow of time within its narrative; what follows is a breakdown of the events in a chronological order whilst also noting when in the story they took place. Much like the main page, Episodes refer to the 3D series, while Chapters refer to the Animated Manga; and italicised lines in a latter part of the timeline notes a deviation to the original take on the scene.
19XX (Manga Chapters 17 & 18)
- Mari becomes friends with a classmate who shares her interest in art.
- Mari struggles to create a painting she really wants to make, where she's found by the classmate.
- Mari remarks to her newfound friend that if she could, she'd take walks in the wood everyday due to enjoying it there.
- Mari also remarks on the "warning from the girl next door" about the woods, and recounts the rumour of the woods, which details the dark history of Aogami.
- The first incident that kickstarts the story's events occurs - Mari is stricken by a headache, but appears to have her inspiration to make her perfect painting...
- ...to be found hours later on the brink of death by her friend, with the canvas, easel and Mari's body covered in blood from the work. Mari expires before she can finish her sentence.
1946 (Episodes 4 to 6; Timeline A)
- Yae witnesses Nanase do something to a girl from another class, who is implied to have approached the Transfer Student following the conversation between Honoka and Sakura.
- Episode 4:
- Shino approaches the Transfer Student, eager to become friends despite her very meek nature. Nanase interrupts the conversation to put the focus on her invitation, before bullying and belittling Shino.
- Sakura and Honoka have an exchange about charms and supernatural topics, then Sakura tells Honoka about the Art Prep Room.
- Yae discusses what she saw happen between Nanase and the other girl.
- Episode 5:
- Sakura notes a "certain mystique" about the Transfer Student before Yae admonishes her for skipping PE class again. After finding out that Sakura went to Art Prep Room, Yae relays the rumour to her about how a student died creating a painting with her own blood and how her spirit haunts it, only for Sakura to become more excited instead of scared like Yae.
- Shino thanks Shiina for helping her find her pencil case, and Shiina tells her to not get near to the Transfer Student for her own sake. Seeing how Shino becomes depressed at the suggestion, Shiina offers to become her friend instead.
- Nanase and Honoka discuss the school's history and what it's built upon, and about the rumour of the Art Prep Room. Nanase decides to check it there and then, but Honoka suggests it would be better to visit the room in a Test of Courage.
- Episode 6:
- Honoka invites the Transfer Student to the Test of Courage, and Shiina volunteers herself into the event; they then discuss how to access the school at a late hour, with Honoka planning to hide and wait for the janitors to leave.
- Sakura approaches Shino, asking the latter if she's noticed anything strange recently; Shino posits that she feels she's subject of bad luck, and Sakura offers her a talisman to ward off misfortune.
- Behind Honoka, Nanase confronts Yae over the latter getting close to whom is implied to be the Transfer Student. Yae voices her concern that Nanase has changed and is acting strange, which surprises Nanase, leading the latter to conclude that Yae is trying to steal her target too and that she must "make [them] all go away" as an Ominous Visual Glitch appears throughout the classroom. When Yae snaps her out of her episode, Nanase leaves the classroom.
1946 (Chapters 6 to 8; Timeline B)
- Shino prays at the shrine to make more friends, and crosses paths with a student whom she doesn't recognise.
- The next day, Shino discovers the girl she crossed paths with is a New Transfer Student. She watches everyone else getting close to the new girl, and after recalling her self-admonishment, takes action to approach the new student herself.
- Several days later, Yae and Sakura discuss the rumour of the Art Prep Room. Nearby, Nanase asserts that the school couldn't be haunted as it was built by the Furukawas, and voices annoyance about Shino being close to the Transfer Student and that she gets headaches looking at her.
- The Day of the Test of Courage:
- The girls (sans the Transfer Student and Honoka) meet at Aogami Station to walk to the school together.
- Along the way, Nanase has a more amicable conversation with Shino, inviting her to the movie and dinner she has planned with the Transfer Student.
- After arriving at the school, Nanase comes down with a headache, worrying Shino. Sakura warns her about walking through the local woods and that her family's company should stop cutting down trees from there to build around Aogami.
- 10:08 PM. After the Art Prep Room rumour turned out to be nothing, Shino checks on Nanase only to be viciously screamed at for "being a nuisance" and to "disappear", which deeply upsets Shino and brings concern to Yae and Sakura, distracting the girls at the wrong moment, as the landslide strikes moments later.
- Later that night, Shino awakens from the ruins and wanders to the shrine, begging for her friends to be saved.
