The main story of the Monogatari Series mostly takes place over the course of an unspecified year. Since it has no set date, this main year will simply be referred to as "Year One."
Approx 600 Years Before Year One
- A princess named Rola laments the fact that people only like her for her looks and not her "inner beauty." She meets a witch who places a curse on her that reveals her inner beauty to people and causes them to kill themselves for being too beautiful. The curse causes a massacre and kills everyone in her kingdom. The infamous "Princess Beauty" sets on a journey to find someone that can cure her of her dreaded curse, accidentally killing off more countries in the process.
- Rola, then taking the name of Acerola, meets a vampire named Deathtopia Virtuoso Suicide-Master who is able to become acquaintances with her as she comes back to life each time she kills her self through vampiric regeneration. Hoping it will lead to getting to eat her, Suicide-Master promises Acerola that she can find a way to cure her of her curse and invites her to stay in her mansion for the time being, treating her as a proper guest. This angers her servant, Tropicalesque Home-A-Wave Dog-Strings, who finds treating humans as anything other than food to be foolish. He attempts to kill Acerola, but ends up completely destroying himself passed the point of regeneration. Feeling guilty, Acerola requests Suicide-Master turn her into a vampire so she can make sure the corpses she creates are not in vain as she'll be able to eat them. The two part ways, and some how or another, the curse is lifted. Under her new name, Kiss-Shot Acerola-Orion Heart-Under-Blade, she be comes an infamously powerful vampire known as the "apparation slayer".
Approx 400 Years Before Year One
- Kiss-Shot Acerola-Orion Heart-Under-Blade arrives in Japan for the first time by jumping from Antarctica. In doing this, she accidentally saves a locale village from a drought when she makes it "rain" after splashing into a nearby lake. The villagers praise her for committing a miracle, and claim her to be a god. She takes the role of a god from then on, hiding her true identity as a vampire. An oddity specialist, known as Seishirou Shishirui, eventually comes to check up on things in the town. Sometimes, Kiss-shot and this man would slay oddities together, implying a bond of sort was made. But eventually, everyone in the village mysteriously vanishes until they are the only two left. An anti-existence known as the "Darkness" then swallowed them in its pursuit for Kiss-shot. The Darkness swallows all of Seishirou except for his hand in which Kiss-shot holds on to as she jumps back to Antarctica. Feeling lonely after what she'd done, she bites into his disembodied hand, reviving him and turning him into her first minion. Outraged upon figuring out the truth and at the fact that he had become a vampire, Seishirou eventually jumps into the sun as an act of suicide and turns to ash, but fails to die.
Fifteen Years Before Year One
- Seishirou Shishirui's ashes drifts back to the town in which he once lived and causes North Shirahebi Shrine to collapse, thus triggering several Apparition cases.
- The Occult Research Club resurrects a corpse as both a tsukomogami and shikigami and names it Yotsugi Ononoki.
- The Shide no Tori finds its next victim, and Tsukihi Araragi is about to be born as its offspring.
- Tsubasa Hanekawa, at around three years of age, is taken into custody by her late step father's wife and her new husband and is given a new family name.
Eleven Years Before Year One
- May 13: (Route X only) Koyomi Araragi and Shinobu Oshino arrive 11 years in the past due to an error on Shinobu's time travel attempt. Searching to rationalize the error, Koyomi decides to try and save Mayoi Hachikuji from her impending death.
- May 14 (Mother's Day):
- Route A: Hachikuji dies in a car accident on her way to her mothers home. She turns into a Lost Cow.
- Route X: Araragi manages to prevent Hachikuji from being run over by a truck and lead her to her mother's house safely. He then proceeds with Shinobu to go back to North Shirahebi Shrine where they manage to use the energy to go back in time, in Route X however.
Seven Years Before Year One
Four Years Before Year One
- Koyomi meets Sodachi Oikura during middle school by successfully answering a "Monty Hall" problem that lead to her house. There she tutors him on math regularly, hoping that he'd notice the discourse of the broken building and alert his police officer parents about her abusive household. He fails to notice and she moves away abruptly.
Three Years Before Year One
- After her family is torn apart from a malicious cult that ruined her mother, Hitagi Senjougahara has a Heavy Stone Crab take her weight away.
Two Years Before Year One
- Sodachi attends Naoetsu Private High School along with Koyomi, Tsubasa, and Hitagi.
- July 15: A study group is organized by a class in which Koyomi, Hitagi and Sodachi Oikura belonged to. A large gap between the scores of those who attended the study group and those who didn't caused a controversy, so a class assembly is held by then class president Sodachi. After the class assembly, Sodachi, through majority vote, is determined as the one responsible for the incident.
- Vampire Kiss-Shot Acerola-Orion Heart-Under-Blade arrives in Japan for the first time in 400 years. Without her knowing, Meme Oshino steals her heart. Weakened by this, she is attacked by three vampire hunters, severing her limbs.
- March 25: On the last day of school and spring break begins, Koyomi meets Tsubasa for the first time after seeing her panties. She becomes his first friend.
- March 26 (early morning): Koyomi finds the injured Kiss-shot and reluctantly helps her. This triggers the events later refered to as Spring Break.
- April 7: The situation with Kiss-shot is resolved
- April 8: The first day of their third year of high school, Koyomi and Tsubasa are in the same class.
- April 11: Koyomi consults Tsubasa about a stone shrine he found in the courtyard
- April 29: Tsubasa Hanekawa has an encounter with a sawarineko. This causes her to "transform" into Black Hanekawa for the first time and triggers the events later refered to as Golden Week.
- May 7: After 3 days of begging, Koyomi manages to borrow Kokorowatari from Shinobu and uses it to confront Black Hanekawa decisively. However, his plan fails and Shinobu is forced to contain her by eating her energy, making Hanekawa forget about the events.
- May 8: Koyomi returns early in the morning Eikou Cram School to get some closure on Hanekawa's affair and comes late to school. There he discovers by accident that his classmate Hitagi Senjougahara was inflicted by an oddity called the "heavy stone crab" that causes her to lose all weight. On the same day, Koyomi takes her to Meme Oshino to perform a ceremony to deal with the oddity. The both of them decide to date.
- May 14 (Mother's Day): After running away from home, Koyomi meets a girl named Mayoi Hachikuji who wants to visit her mother's house. With the help of Meme and Hitagi, Koyomi determines that she is an oddity called "lost cow" and is in fact a ghost of a girl who was killed in a vehicular accident. Mayoi manages to locate her mother's house and passes on, only to return as a wandering ghost.
- May 22: Suruga Kanbaru, an underclassman and admirator of Hitagi and possessed by a Rainy Devil, attack Koyomi due to being jealous of him dating Hitagi.
- Mai 23: After being confronted by Koyomi, Kanbaru is brought to Oshino who reveal the nature of her Apparition. Koyomi is almost beaten to death by Suruga in an attempt to exorcise the Apparition but end up being saved by Hitagi.
- June 11:
- Meme Oshino ask Araragi and Kanbaru to repay their debt by putting a talisman on the North Shirahebi Shrine. They cross path Nadeko Sengoku and discover after putting the talisman that the shrine was being used as a sacrificial altar with snake corpses.
- Meeting with Hanekawa in a book store to by study guides, he consults her about the matter and she inform him that it was probably a ritual. After parting, Koyomi sees Sengoku looking at curse books and decide to confront her with Kanbaru the next day.
- June 12:
- Kanbaru and Koyomi go back to North Shirahebi Shrine and confront Sengoku who informs them that she was cursed by a classmate after rejecting a boy. After consulting with Oshino, Sengoku Kanbaru and Koyomi perform an exorcism ritual but realize almost too late that she was actually the victim of two curses. Koyomi is forced to use his power to separate the remaining snake that return to the curse placer, the boy who confessed to Sengoku.
- June 13:
- On lunchbreak, Hitagi informs Koyomi that they would go on their first date that evening.
- At school end, Koyomi meets in front of the gate Sengoku who thank him for his actions the previous days. She runs however when Hanekawa arrives. After talking about his relationship with Hitagi, she is overrun with a powerful headache, leading Araragi to fear a ressurgence of Black Hanekawa.
- That night, Hitagi has her father drive them to their first date and when alone, Hitagi's father entrust her to Araragi. Stargazing together alone, Hitagi and Araragi reaffirm their love.
- June 14: Tsubasa, due to silently suffering Koyomi and Senjougahara relationship, is afflicted by cat ears but Araragi realises the threat and take her to Oshino who reveal and restrain Black Hanekawa. To contain her once more, Koyomi must borrow Shinobu's power.
- Route A: Having met Hachikuji in the morning, he gets information soon enough about Shinobu disappearance to search for her. Forcefully provoking Shinobu's intervention, as she was hiding in his shadow, Black Hanekawa is contained once more, and Shinobu decides to henceforth live in Koyomi's shadow.
- Route X: Due to never having met Hachikuji in this timeline, he doesn't realize Shinobu's disappearance in time and thus die to Black Hanekawa, triggering Kiss-shot to return to her former strength. She goes berserk and creates minions that spread like a zombie infection, leading to the world's end in one night.
- July 29:
- August 14:
- August 20:
- On the night before the 21th, Koyomi goes to North Shirahebi Shrine on the advice of Shinobu to go back one day in the past to finish his homework in time but end up triggering the events of Mayoi Jiangshi by going 11 years in the past.
- Unknown to them, Seishirou Shishirui, who had taken refuge in North Shirahebi Shrine, saw Shinobu, which triggered him to finally take physical form.
- August 21:
- Route X: Returning from 11 years before, Araragi and Shinobu arrive to see that due to a butterfly effect, the city is in ruins. After scouting the city, they manage to deduce that the world ended somehow due to their saving of Hachikuji on June 14. However, when they try to go back to North Shirahebi Shrine, they discover that Hoshino gave this timeline Araragi a more powerful talisman that led to the disappearance of the Apparition energy. Surrounded by zombies, they escape by flying using Shinobu's powers until sunrise.
- Route A:
- Koyomi arrives back after resolving the Mayoi Jiangshi incident and cross path with Hachikuji near North Shirahebi Shrine. Arriving home to give her backpack back, they are confronted to a "Darkness" and thanks to Ononoki, escape to Eikou Cram School where Shinobu reveals the events of 400 years ago. They are forced however to escape once more, this time to the mountains, but Koyomi's link with Shinobu is severed.
- Tsubasa Hanekawa meets a tiger-shaped oddity and this encounter triggers the burning down of her house. Not wanting to bother anyone, she decides to sleep in Eikou Cram School. Unknown to her, the events reawaken Black Hanekawa for the third time.
- August 22:
- Route X: Shinobu deduces that the world's end is her fault and explains to Araragi her point of view during the events of June 14. Araragi formulates a plan to search for survivors that comes to fruition on August 26.
- Route A:
- Koyomi travels down the mountains with Hachikuji and Ononoki and send a mail to his close friend and family to not worry them. Wandering the mountains, they finally meet Izuko Gaen and ask for her help, which she agree on the condition of three favors from Koyomi. She then proceeds to explain them the nature of the "Darkness", convincing Mayoi to pass on to the otherworld.
- After sleeping in Eikou Cram School, Hanekawa is scolded by Senjougahara and skip school with her, staying at her place. Later that day, they both receive the mail from Koyomi.
- That night, Black Hanekawa meets Kako and upon returning is confronted by Senjougahara who decides to let her act without informing Hanekawa.
- August 23: (Route A only)
- Hanekawa learns that Koyomi has requested the assistance of Kanbaru and decide with Senjougahara not to act. Later that day, she is welcomed in the Araragi household by Karen and Tsukihi and sleeps in Koyomi bedroom.
- Kanbaru meets with Koyomi that night due to one of the favors he owed to Gaen and both are confronted by Seishirou Shishirui before being saved by the timely intervention of Kako and Ononoki. To her urge, they proceed to go meet with Izuko Gaen, only to wander due to a curse from Seishirou.
- While Koyomi and Kanbaru are lost, Black Hanekawa meets Shinobu who was waiting Koyomi in his room since the events of Shinobu Time and the both of them decide to join him in Eikou Cram School. They, however, arrive too late and the building is already burnt down. They then proceed to Namishiro Park where they are confronted by a monkey apparition and defeat it with the help of Ononoki.
- 3 hours after leaving the cram school, Kanbaru and Koyomi finally arrive at Namishiro Park where they join with Shinobu and confront a half-crab half-monkey apparition that Koyomi defeats after being entrusted Kokorowatari. Shinobu then defeats the Jagirinawa that rises from its corpse. After discovering Gaen message, they then proceed to North Shirahebi Shrine.
- Koyomi, Shinobu and Kanbaru arrive to North Shirahebi Shrine where Izuko lie to them by introducing herself as Oshino's little sister. She then proceeds to explain to them Seishirou's circumstances.
- August 24: (Route A only)
- Hanekawa deduces from her traces the resurgence of Black Hanekawa. On her way to school, she meets with Episode and Gaen. After discussing with them and the Fire Sisters, she manages to deduce the nature of Kako.
- After being explained the circumstances of his case, Araragi is asked to do errands for Kanbaru and Shinobu and bumps into Seishirou in human form in a bookstore. After preventing him from poisoning Koyomi, Episode and Gaen manage to set up a duel between the two of them that same night.
- Going back to Shirahebi shrine, Araragi witnesses, secretly with Ononogi, Kanbaru's confrontation with Shinobu. After a long argument, she manages to convince her to face Seishirou once and for all.
- At night, Hanekawa decides to entrust everything to Black Hanekawa by writing her deductions in a diary. She decided to acknowledge her weaknesses and ask her to bring Kako and herself back to being a part of her. Before going to sleep, she changes into Araragi clothes and send him a picture of herself in his room.
- At the same moment, Araragi, Episode and Gaen meet with Seishirou in Naoetsu's playfield. Koyomi decided not to restore his bond with Shinobu so that he would fight with his own power. Upon realizing this, Seishirou decide to give him an handicap and let Gaen decide the duel rules. Which she decides to be one-hit duel with a disputed bamboo sword. However, just before the duel, Shinobu shatters it, replacing it with Kokorowatari. Despite the huge physical advantage of Seishirou, he manages to defeat him by using Oshino's Talisman, which he took from the shrine. Just before he vanishes however, Shinobu reveals herself to him and eat his remains, forgiving him once and for all.
- Just before the duel, Araragi receive the mail from Hanekawa and is explained the circumstances by Kanbaru and Gaen. Being pushed by the later to abandon the duel to save her, he decides to entrust the affair to Kanbaru and resolve the duel before heading to save her. After rejoining with Kanbaru, he sends her to protect Senjougahara while he joins with Hanekawa.
- Meanwhile, Black Hanekawa confronts Kako as he is about to burn Tamikura-sou. Despite Hanekawa trying to convince him to return by overtaking Black Hanekawa and Black Hanekawa using her drain, he overwhelm them both, sending them flying to a railroad, but before he can finish them off, Araragi arrives and pierce him with Kokorowatari. With him reassuring her that he would always accept her whatever she would become, and her finally confessing his feelings to him only to be rejected, she absorbs Kako, leading her to being hurt and cry for first time.
- August 26: (Route X only)
- Araragi and Shinobu launch fireworks at Namishiro Park on a cloudy day to signal themselves to potential survivors but end up attracting a horde of zombies. They are saved by an adult Hachikuji who ironically is the only survivor in the city. She reveals that she was waiting for them as Oshino deduced something from her tale of Mother's Day 11 years before. However, he was incapable of preventing World's End and entrusted his hopes to Hachikuji before launching a suicide mission against Kiss-shot who somehow survived an attempted suicide with the help of Kagenui and Kaiki. Anticipating his failure, he ask the both of them in a letter to confront Kiss-shot in his place.
- After parting with Adult Hachikuji, Araragi and Shinobu go back to North Shirahebi Shrine to confront Kiss-shot. However, when she appears, she loses her will to fight after seeing for the first time hope of a better future. To allow them to go back to Route A on August 21, she lets Shinobu eat her, freeing at the same time all the zombies from their slavery and returning them to normal, thus giving Adult Hachikuji the good world they wanted to give her, as well as Kiss-shot the death she longed for.
- Late September: Koyomi Tree
- October 24:
- October 31:
- January 1: Deishuu Kaiki starts his operation to deceive Nadeko Sengoku into not killing Araragi Koyomi and his friends. He ultimately succeeds and Nadeko turns a new leaf to follow her dream as a manga artist and forget about Koyomi.
- February 13:
- April 9-21: