2011 | Manga
Ortho Siblings full body view
Ortho Siblings



Oroso Kyōdai

Japanese Voice

Makiko Ohmoto (Sister)
Masaki Aizawa (Brother)

Manga Debut

Chapter 238

Anime Debut

Episode 101 (2011)


Male and Female Male and Female

Eye Color

Green (Female)
Yellow (Male)

Hair Color

Blond (Both)



Previous Occupation

Chimera Ant Officers




Dart De Darts

Image Gallery

The Ortho siblings (オロソ(きょう)(だい), Oroso Kyōdai) were a pair of Chimera Ant siblings who resided in an Underground Lake in the Republic of East Gorteau.[1]


They had features of aquatic animals. Both of them had scales covering their legs as well as webbed feet. Scales also covered the older brother's arms while the sister's were left bare.


The brother was quite sadistic, wondering why Killua wasn't screaming,[2] and expressing that he wanted Killua to die in fear.[3] The sister was very trusting of her brother, and was proud of his abilities. They both loved each other very much and their confidence spawned from it.[2] However, once defeated and decapitated by Killua, they lost all respect for each other and began bickering.[4]


Chimera Ant arcEdit

Ortho siblings base

The siblings playing their dart game inside their base

After Remora successfully attaches the "Bar Double Bull" badge on Killua, the Ortho siblings are revealed and the brother begins their conjunction Nen ability Darts De Darts.[1] After Killua washes ashore a sound goes off in his head; he's immediately hit with two large fish like darts on his left hand and chest and realizes his entire body has become a dart board. The brother then telepathically speaks to Killua and inquires if he has any clue of what's happening to him. In the siblings base, the brother removes the darts off the dart board and re-throws the darts, piercing Killua's right shoulder and both of his thighs. As the brother pierces more of Killua's body with the Fish Darts, he asks if he's figured out what kind of attack he's being struck with. Killua manages to get near and look into a nearby pool of water to deduce it's a game of darts and the brother confirms it.[2]

The brother then explains to Killua that he can't do anything against his ability even if he knows it because his darts only materialize when in contact with the target and after a dart pierces Killua's left shoulder, he details it was worth worth 54 points and the targets on his board are linked to various parts of his body. The brother pierces Killua's elbow worth 27 points, the back of his right hand worth 18 points, making a total of 99 points. Back at the siblings base as the brother continues to rack up points, the sister seated upon a bar stool, praises him. The brother then boasts that the two of them are invincible and the sister claims it's because they're bound by a strong sense of trust.[2] With the game close to the end the sister asks her brother if they should tell Killua about it. However the brother rejects the idea to torture him further so he could have better concentration playing and continues to throw a dart onto the board hitting Killua's left arm, chest and right leg.[3]

On the final turn the brother hits Killua's left ear for 18 points, the right calf for 7 points, and finally the forehead for 20 points. This ends the game and the siblings win, celebrating with their special clap together. The siblings then leave their base to check the body of Killua whom lies on the ground with a dart sticking out his forehead. The brother contacts Flutter and informs him of their accomplishment and Flutter praises their actions and informs the siblings he'll inform Leol and convince him to have them promoted to Assistant Squadron Leaders. The siblings celebrate the fact they'll become higher ranked and then start to preform their special clap again only to have their heads severed by Killua at the end. The brother demands to know how Killua managed to survive when a dart is sticking out his head. Killua pulls the dart from his head reveals he used a suction cup from an octopus.[3]

Killua takes the Ortho siblings's heads off

The Ortho siblings killed by Killua

The brother then asks how Killua was able to pull off such a trick when his darts are impossible to dodge. Killua explains he didn't dodge the final dart, after figuring out the final dart was aimed at his head, he cultivated a new Hatsu named Godspeed to optimize his reaction speed, allowing him to stop the dart the moment it touches his skin. The brother inquires what's Killua darting experience. Killua replies that at age six he mastered the game.[3] The siblings then argue and insult each other blaming the other for losing the game and when Ikalgo rescues the incapacitated Killua the siblings try to convince him to save them instead, but only anger him for calling him an octopus.[4]

Abilities & PowersEdit

Being Chimera Ants with the genes of fish, the Ortho siblings could breathe underwater and were immune to water pressure to a certain extent. Like other Chimera Ants, they seem to feel no pain even if mutilated, as their heads continued to bicker after being severed. The brother was exceptional at throwing darts.


The Ortho siblings' combine their Conjuration abilities in a single Hatsu.

The Ortho Siblings's Nen Abilities
Type: Conjuration Darts De Darts (死亡遊戯 (ダツDEダーツ) Death Games)
Ortho siblings badge
Ortho siblings base
Ortho Siblings nen on Killua
Their nen abilities work in conjunction—the sister conjures a tag that when placed on someone, will link her brother's conjured dart board to the target. The tag cannot be removed until the game ends, not even by themselves. The brother can then shoot the fish-like darts made from his aura at the board and cause damage to the target according to where the darts hit the board. There is no way to avoid the dart because it doesn't exist until it touches the targets body. The siblings run a considerable risk playing the game since if the older brother misses the last shot to end the game, all the damage accumulated on the target until that point will be carried over to themselves.[2]


  • Their ability is likely based on Kaname Hagiri, an antagonist on YuYu Hakusho, another manga created by Yoshihiro Togashi. Hagiri was capable of marking his victims with targets and shooting projectiles that would automatically aim for those targets.
  • The dart game they were playing were a 01-501 game. The game starts with 501 points and the goal is to reach zero.


  1. 1.0 1.1 Hunter × Hunter - Volume 23, Chapter 238
  2. 2.0 2.1 2.2 2.3 2.4 Hunter × Hunter - Volume 23, Chapter 239
  3. 3.0 3.1 3.2 3.3 Hunter × Hunter - Volume 23, Chapter 240
  4. 4.0 4.1 Hunter × Hunter - Volume 23, Chapter 241


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