Timeline

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This article contains plot details about an upcoming episode.

1582[]

One year after the death of Oda Nobunaga, the events of Choubu no Shinobi happen.

"Yoriko" is born in the 1910s.
With her mind control powers, Yoriko takes over Japan's goverment and eventually wages war with Hideki Tojo as Suzumebachi. She gets Hiroshima and Nagasaki nuked on purpose.
Right after WWII, Yoriko adopts Ushijima Masashi and establishes the Organization with him.
In the late Nineties, Ushijima is replaced by Jin Togawa. Alice is born some months later on a 12th of December.
Dinoponera is born the day after Alice does. A year later, her home village is destroyed. Paraponera finds and adopts her.

Imomushi battles against several Organization members in the Ageha cruise ship.
On Alice's 15th birthday, her mother Ayana is killed by Suzumebachi on Yoriko's orders.
On the next year's May, Kumo trains Alice for two very productive weeks and then dies by her hand.
Sara had been admitted to Ouran High on the last week of April. While Alice was in training, Sara meets Kuramoto, becomes her servant and is made to win the Student Council President election thanks to a "gaudy festival".
Chiyuri comes across Dinoponera 8 hours before the zombie outbreak.
A week after defeating Hibiki, Alice faces the Arachnid Hunt. According to an omake in Arachnid Volume 8, it starts on May 29 at 15:00.
Imomushi tries to kill Suzumebachi for lying to her about Mika's fate, but gets knocked out. Suzumebachi lets Hanakamakiri take her alive out of the Ouran school, in exchange for Hanakamakiri helping Alice become the boss later.
Once the Arachnid Hunt ends and Yoriko is dead, the Army Ants' zombie pandemic begins to devastate Japan.
28 days after the zombie apocalypse starts, Alice decides to go out and fight against the Organization once more.
Around 58 weeks since the outbreak, Alice is saved by Hanakamakiri who then declares her the new Boss.
Kabutomushi and Gokiburi are seen looking for Alice afterwards.