Sasaki Kojirou



  • Class: Assassin
  • True Name: Sasaki Kojirou
  • Gender: Male
  • Source: Historical fact
  • Region: Japan
  • Alignment: Neutral Evil
  • Height: 176 cm
  • Weight: 63 kg


  • Setting creation: Nasu Kinoko
  • Original character design: Takeuchi Takashi
  • Character design: Mata
  • CV: Miki Shinichiro
  • Main works appearance: Fate/stay night, Fate/hollow ataraxia, etc


Magical PowerE
Noble Phantasm?

Class Skills

Presence Concealment: [D]

Suppresses one's presence as a Servant. A Skill suitable for covert action.

Personal Skills

Mind’s Eye (Fake): [A]

Resistance against corrections[1] caused by vision obstructions.

It can be also be defined as a sixth sense or premonition[2]; sensing danger by means of natural talent.

Vitrification: [B+][3]

Serene and clear, as a polished mirror and still water. A mental defense that invalidates mental interference.

While he may not be an assassin in the traditional sense and thus unable to make use of the Assassin’s ability of “Presence Concealment”, he is able to conceal his presence utilizing a martial artist’s state of empty mind[4].

Knowledge of Sowa: [B][5]

A special technical skill which prevents the degradation of accuracy regardless how many times the same technique has been used against the same enemy.
His attacks becomes imperceivable.[6]

TL Notes

[1]as in DnD style dice roll probability correction

[2]虫の知らせ. Random trivia: it’s a jp ancient concept that there is a bug living inside you that has various effects on your emotion and consciousness. More info in new window

[3]透化 is actually a legitimate scientific term for when things went under excessive cooling after a fusion process, turning into glass-shaped amorphous substance. Hence, vitrification.

[4]An add on info from CM3 for Vitrification and Presence Concealment D: “Since he is not a true Servant Assassin, this is not a class ability. It is his intrinsic ability as a martial artist to “cut off his presence”. This is not a skill to hide, but a technique of the mind for the martial artist to merge with his surroundings.”

[5]宗和 is a weird concept. Like, I cant find actual encyclopedic entry of that term, only a tea ceremony style which is a stretch. However, individually the kanji 宗 means principle/center/pillar/meaning, whereas 和 is an actual concept, which translates best into Harmony. It implies a peaceful unity and conformity within a social group, in which members prefer the continuation of a harmonious community over their personal interests.

[6]add on info from game: “Perhaps, it was such a sword mastery that other’s simply cannot become accustomed to it.”

Noble Phantasm(s)

Tsubame Gaeshi - Swallow Reversal

  • Rank: -
  • Type: Anti-Unit Mystic Sword
  • Range: 2
  • Maximum target: 1 individual

Tsubame Gaeshi.

A special move that cuts down the enemy from three directions simultaneously. It is not simply a “swift” slash; it truly happens simultaneously.

In order to achieve his goal of cutting down a swallow midflight with a longsword, the nameless swordsman who became the basis of this Heroic Spirit personality underwent an outrageous, straightforward training. This is the mystical sword that he had acquired at the end of it.

In the world of magic, it appears to be one of those known as multidimensional refraction phenomenon.



  • First pronoun: watashi
  • Second pronoun: omae/kisama/** (no honorifics)
  • Third pronoun: omaetachi/kisamatachi/** (no honorifics)


An elegant man, wrapped in a refined jinbaori, fond of the aestheticism of nature.

He is an enigmatic figure who, while calling himself as Sasaki Kojirou, the swordsmaster who wield at will the longsword referred as the Monohoshizao[1] and rumoured to be unparalleled during the Keichou era, also proclaims himself to not be Sasaki Kojirou himself.

His character is detached and elusive. And while he would make remarks that could be taken as making a pass at female Servants such as Artoria or Medusa, he would also be quite troubled and at loss as to what to do should a passing by female high schooler tries to befriend him.

In the Fuyuki Holy Grail War which has been structured to have only “Hassan-i Sabbah” summoned in the Assassin class, he is an irregular existence; however, this is due to him being summoned as the familiar of Caster, who had intervened with the system of the Holy Grail War.

While his true identity is a nameless swordsman who had existed in the same period as Miyamoto Musashi, he is also the nameless swordsman who due to being able to put together the hidden sword of Tsubame Gaeshi, said to be the technique used by the swordsman Sasaki Kojirou, had been summoned as the Heroic Spirit Sasaki Kojirou.

Because he had been summoned with the main temple gate of Ryuudou Temple in Fuyuki City as the catalyst, while he is unmistakably someone with a connection to Ryuudou Temple, due to being summoned with the name of “Sasaki Kojirou” he does not even know of his own name.

However, the man who would abase himself as a bearer of the wicked sword does not feel affected by it, nor does he lament that his attained feat--of bringing about the multiple refraction phenomenon known as Tsubame Gaeshi with only a human body and without being a magus--made to be the feat of someone else. He simply performs the role of Sasaki Kojirou calmly and composedly.

[1] literally means clothesline

Attitude Towards Master

Due to him not being an existence that manifested by means of the Grail, he does not possess a wish towards the Holy Grail to begin with.

Put to words, one can say that it is due to being summoned by Medea that the Heroic Spirit known as Sasaki Kojirou was born.

While he is faithful towards the Master, there’s also another aspect of him that abide to the Master because it is a contract made by magical means and because he has no reason to disobey the Master.

However, as expected, it is but a human nature for wanting to see what sorts of fate his mystical sword that he had tempered so thoroughly would brought about. He is fond of a fair and square bout against those he had deemed as strong.

And thus, should he become unable to do so due to the Master’s order, there are cases where he would abandon said order as much as his contract would allow him, even as he suffer the guilty conscience as a result.

Dialogue Examples

“----------Servant Assassin, Sasaki Kojirou.”

“While I do pride myself in that none can best me in the bout of the mind, it is quite unfortunate that tactics are part of being a warrior. Such things are not unusual upon the battlefield.”

“Not even swallows are able to escape my blade. This would be quite the unfair match, wingless as you are.”

Historical Character and Figure

Sasaki Kojirou is a figure who had been reported to had fought and been subsequently defeated in a duel against Miyamoto Musashi at Funashima (Ganryuujima) during the year 17, month 4, and day 13 of the Keichou era. Unlike Musashi, his real figure was unclear, and although it is said that he made use of the hidden sword of Tsubame Gaeshi with a longsword 3 shaku long, nothing about said technique is actually known.

In short, Sasaki Kojirou had been created and put together by multiple literature source in regards to Musashi; substantially, an imaginary swordsman.

And by being able to bring about the Tsubame Gaeshi, said to be used by Kojirou, as a result of his training, this Heroic Spirit known as “Sasaki Kojirou” had been summoned as an existence that fulfill the role of the imaginary Heroic Spirit; the nameless, genius swordsman of Fuyuki origin.

Character in FGO

During Fate/Grand Order first service commencement awaited an unexpected development; on the first chapter “Evil Dragon Hundred Years War Orleans”, the easily attainable 1 star Assassin Sakaki Kojirou was highly valued against the the Rider-class Wyvern flock that kept on harassing the player, and thus he was revered with the alias Dragonslayer. Thank you, Sasaki Kojirou. THY ARE THE DRAGONSLAYER.

Depiction in previous works

He had a roughly similar setting and role on the Fate/stay night’s prototype novel. In Fate/stay night, he was summoned by Caster, and then proceeded on having an east-meets-west swordsmanship showdown in the midst of the story’s climax. On top of being an irregular summon, he was restrained due to being unable to leave the main gate of the Ryuudou Temple. However, in the anime Carnival Phantasm, by utilizing a drastic move of loading the whole temple gate on a truck, he had managed to obtain freedom.


Once, she was his summoner. Had she not summoned upon a nameless swordsman, then this Sasaki Kojirou would have never come to be. In a way, he felt a debt of gratitude towards her.


She is unaffected and sincere, while filled with fortitude and vigor; truly excellent. Her attitude, too, is dignified and centered, steady and unwavering.

However, that brusqueness of her is her one true flaw ooOoOUCH!?

Miyamoto Musashi

There was never a time when they encountered each other; but as he is Sakaki Kojirou, Miyamoto Musashi is an opponent he simply cannot ignore. He would love for a bout where they put their life on the lines.

Comment from the Illustrator

He sure played an active role during the first chapter, huh. He had really helped me a lot as well.

You can say he sure isn’t lacking in for some good gag during interludes and dango quest. Still, his feature is actually on the slim side; he got those slit, almond eyes and beautiful silky hair. He’s all around a beautiful character. Also, I was like, totally surprised when he acted affectionate in My Room. By the way, would Anchin-sama never get implemented, I wonder. (Mata)

Material Images