This player, Seira, is property of PercyJacks.

One-Cut Killer
Personal Info
Name Otosaka Yukiko
Kanji 乙坂 雪子
Romanji Otosaka Yukiko
Birthday November 16
Age 14 (Beginning of Always Deadly Arc)

16 (End of Always Deadly Arc)

Gender Female
Height 169cm
Weight 53kg
Eyes Faded Teal
Hair White/Light Pink/Light Blue
Occupation Student
Family Yumiko Otosaka (Younger Sister)
Player Profile
Display Name Seira
Kanji セイラ
Romanji Seira
Epithet One-Cut Killer
VRMMORPGs Played Sword Art Online
Occupation Clearer
Status Alive
Unique Skill Endroll
Unique Weapon Shattered Mirage
Voice Actor Rina Satou
First Appearance Sword Art Online: Always Deadly

I became stronger so I wouldn't have to lose anyone, and yet…
~ Seira

Seira (セイラ, Seira) was one of the top floor clearers in Sword Art Online.


Originally, Seira’s character had a face that looked like her own, but still was different. Seira has white hair that splits off into light blue and light pink colors and reaches just below her underarms. Her eyes are a faded teal, giving them a sort of ghostly or ominous look. She wears black sleeveless armor with a dark skirt and a magenta collar-like scarf around her neck. Her gloves are black and fingerless, with her right extending past her elbow. She also always wears a black beret with one teal stripe and one magenta stripe, with a grey visor.


Seira usually emits a cold aura around her, preferring to work alone on the front lines rather than make or join a party. She's also somewhat of a tsundere, not wanting others to know her true feelings so that they wouldn't try to get closer to her. This makes her stubborn and headstrong, always thinking that she can handle things by herself. Which is mostly true.


Before Seira went into Sword Art Online, she never really had an interest for anything. Due to this, she went along by herself rather than finding any friends. She preferred it that way. Relying on her intuition, she never really got any grades that were especially good, and thought of studying as something that she didn't need to do. Her family had financial problems, so Seira often never had time to study, and barely squeezed in time for her homework. As a result of saving all her allowance for an entire year, she was able to buy a NerveGear and Sword Art Online. Since she was trapped in the death game, her parents decided to have another child, Seira's sister Yumiko.

When Seira got into the game, she decided that it was another world, so making friends, or at least allies, was acceptable. She found another group of friends and joined their party, but she was treated as more of an assistant than a person. Seira was still grateful to them though, for accepting her into their party. When she learned that everyone was trapped, she stayed with her party and did her best to help them. However, they all got killed on the first floor due to the stupidity of the leader. Seira grieved by herself, and deemed companions unnecessary to survive in Sword Art Online. She avoided interaction with others, and kept herself at a distance when she had to be with more people. Upon receiving the Unique Skill Endroll, her killing ability became so wide-known that every player who did see her treated her as some sort of celebrity or goddess. Her opinion on having other members in her party didn't change, so she rejected every friend request, party request, love confession, and guild invitation. That didn't stop the other players from trying again, though.


Aincrad Arc

Seira was one of the most determined players to clear the game. She farmed monsters and trained every time she could, rarely allowing herself to rest. She also provided most of the labyrinth map data for each floor. By slaying so many monsters, by the 50th Floor, she gained the Unique Skill «Endroll», which lets her one-hit-kill most enemies and instantly defeat some players in a duel.


Nedelin – Seira had seen and heard of Nedelin before, since she heard of the “Orange Blur” that fought extremely well during the fight against the 39th Floor Boss. The only reason she wasn’t there was because she overslept during the day of the battle and the doors to the boss room wouldn’t open. She thinks Nedelin is a good player, but doesn’t like his laziness. However, she would rather be with him than some of the other front liners.

Phage – (They haven’t met yet)

Nemesis – (They haven’t met yet)


Seira was able to deal with any opponent very quickly, so she always used minimal movements in order to conserve her energy. Her sword style was light, but sometimes filled with power for insurance that it would hit. Favoring speed over power due to her already overwhelming power, she moves swiftly and precisely, to ensure that all her energy wouldn't go to waste. Also, knowing that her sword is her biggest weakness as well as her biggest strength, she also has some martial arts skills prepared.

Sword Art Online

  • Level:95
  • HP:12450

Main Equipment

  • Shattered Mirage


One-Handed Straight Sword Battle Healing Blade Throwing Parry Searching
999 / 1000
813 / 1000
368 / 1000
901 / 1000
821 / 1000
Tracking Hiding Martial Arts Light Metal Equipment Sprint
631 / 1000
799 / 1000
844 / 1000
756 / 1000
771 / 1000
Acrobatics Cooking Endroll
918 / 1000
610 / 1000
964 / 1000

One-Handed Straight Sword Skills

  • One Flash
  • Pulse Trigger
  • Strike Mirror
  • Razor Wave
  • Execution Sequence
  • Thousand Ram
  • Stalactite
  • Vertical
  • Descent Quake
  • Curtain Call

Martial Arts Skills

  • Correctional Strike
  • Missile Kick
  • Roundhouse Launch
  • Flip Counter
  • Bullet Fist
  • Anti-Material Strike



Music Theme

【Lily V3】Betrayer Module ウラギリモジュール【Vocaloidカバー】

【Lily V3】Betrayer Module ウラギリモジュール【Vocaloidカバー】

【IA ROCKS】セツナドライブ【オリジナル】

【IA ROCKS】セツナドライブ【オリジナル】

Calling my Twillight - Taimadou Gakuen 35 Shiken Shoutai ED Full

Calling my Twillight - Taimadou Gakuen 35 Shiken Shoutai ED Full

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