Seishirou Shishirui was Shinobu Oshino's first vampire minion and the original oddity slayer. He was an afamed oddity specialist in his time.

Third and “Final Season” of the Monogatari Series, part 3/5. Contains the arcs Ougi Formula, Sodachi Riddle, Sodachi Lost and Shinobu Mail from the Owarimonogatari light novels.
 
During the month of October of his third year in high school, Koyomi Araragi is introduced to a transfer student named Ougi Oshino by his underclassman Suruga Kanbaru. Ougi tells Koyomi that she has something she wishes to consult with him. When she draws the map of Naoetsu High School, she finds something peculiar on there. This discovery reveals a tale that wasn’t meant to be told, and this makes Koyomi’s high school life totally different. This is the story that brings to light “what” makes Koyomi Araragi. This is the story that reveals the “beginning” of everything.
 
(Source: Aniplex)
 
Note: The first episode aired with a runtime of ~48 minutes as opposed to the standard 24 minute long episode.

__Height:__ 173 cm (5'8'')  
__Non-anime roles:__
-Taiga Saejima - Yakuza


One day, high-school student Koyomi Araragi catches a girl named Hitagi Senjougahara when she trips. But—much to his surprise—she doesn’t weigh anything. At all. She says an encounter with a so-called “crab” took away all her weight …
 
Monsters have been here since the beginning. 
Always. 
Everywhere.
 
(Source: Kodansha USA)

It, like the dark that makes up most of the cosmos, is not an aberration. Nonbeing can swallow you whole, yet if anything, it’s the anti-aberration. Darkness, in fact, is the Law, an executioner from whom a mark can try to run and hide, but only for so long. When it comes calling, the fortunate just might have the time to say goodbye. And the Darkness is—here now. Before ever visiting Japan to find a place to die, four centuries, indeed, before her failed suicide attempt, the legendary vampire KissShot literally stepped foot on the land of the rising sun with an epic jump that ended a lonely sojourn in Antarctica. It was back in those days that the proud noble created her first thrall. It was then, too, that she first met the Darkness.
 
(Source: Kodansha USA)

Volume 1: 
Before we witness the series’ climactic showdown in the third volume of the End Tale—each part of which forms its own cohesive whole—narrator Araragi wrestles with a crucial bit of history that had turned him into the loner we met at the very beginning, who opined that friendships only lowered his intensity as a human.
 
What initiates his pilgrim’s progress of a reckoning is his first encounter, at school, with the mysterious freshman Ogi Oshino, self-described niece of the equally enigmatic aberration expert Mèmè, and the book’s opening chapter is a harrowing standalone novella of a who-dunit involving a locked room of sorts.
 
Our increasingly well-adjusted hero kept on beingdecent at one thing even when he was just hanging on, but this forte, an unlikely aptitude for math, of all things, becomes the focus of a cheating scandal and a web of recollections that forces him to come to terms with, what do you know, his capacity to connect to people.
 
Volume 2: 
When an old flame who gave up on life and chose to go up in flames—because he wanted to leave you but couldn’t—comes crawling back after four hundred years, you might not appreciate it, especially if you’re in a new relationship. But nothing’s ever simple between people, and that’s even truer between monsters.
 
For the first time in months, our heroic loser Araragi is human, parted by previous events from the ex-legendary vampire bound to his shadow. Before he, the second-ever thrall of the former Kissshot, can resume his partnership with the donut-loving waif that she’s turned into, she must make a choice—about that first-ever. 
 
Before the End Tale can end, some loose ends must be tied, and in this volume, the fixer Gaen calls in her favor, requesting an introduction to her niece; the errand of the amulet that Araragi ran with Kanbaru comes into crisp focus; and the time-traveling and -spanning Dandy and Demon Tales see their devastating resolution.
 
Volume 3: 
No good deed goes unpunished, they say, and so does friendship and lowering your intensity as a human, they don’t say—alas, for all his literally painful hustle and inveterate need to save others, our brave fool of a hero ends up in hell, a conception of the inferno in its full Buddhist glory, and muses (lol) if there’s a return ticket.
 
Told in three chapters, the final part of End Tale concludes the story proper and resolves the series’ panoply of ongoing mysteries: the dues of a do-gooder for relying on a power not his own, the identity of a shady transfer student, the outcome of a class president’s questing abroad, and even the true name of a park.
 
Araragi, indeed, is the one who knows, but along the way he meets old faces, really every last one of them, who aid him on his journey for understanding, and perhaps for salvation, and you for one might not be surprised if he had another rendezvous with an erstwhile “cloistered princess” before it—guess what it is—sees an end.
 
(Source: Kodansha USA)

Music video for the song Undead by YOASOBI.

The song was used as the ending theme of the anime Monogatari Series: Off & Monster Season.