Sakon and Ukon

and the older brother are twin brothers who share positions in The Sound Four (Orochimaru's bodyguards). To help distinguish between the two, Sakon wears beads around his neck and Ukon has a somewhat deeper voice. Also, their bangs are on oposite sides (Ukon's being on the left, Sakon's on the right).

Personality
Sakon and Ukon enjoy bad-mouthing the opposition. Orochimaru notes Sakon to be the fastest and strongest member of the Sound Four, traits Sakon is very proud of. When in battle Sakon likes to prolong the fight by toying with the opponent and use unnecessarily powerful techniques. This tendency of Sakon's causes him to slow down the rest of the group whenever he gets interested in an opponent. Ukon is able to counteract this flaw by being more impatient and hasty than his brother, forcing Sakon to quickly end his battles.

Sasuke Retrieval Arc
During the Sasuke Retrieval arc, Sakon and Ukon fight and almost kill Kiba Inuzuka and Akamaru. Before they can finish the two off, however, Kankuro with his puppets Karasu and Kuroari arrive and kill them both, saving Kiba and Akamaru.

Abillities
With their kekkei genkai, Sakon and Ukon are able to merge with the bodies of others. Ukon generally uses this ability to remain within Sakon's body where he can bring out some of his body parts to aid Sakon in blocking or attacking. Ukon can separate from Sakon's body so that the two can attack independently, though he is not used to moving on his own and thus tires easily.

Like the rest of the Sound Four has Sakon and Ukon been given Orochimaru's cursed seal. Both have the same type of cursed seal, which consists of three bean-shaped dots which seems, that seems to be hidden under his hair on the right side of his forehead for Sakon and under the left side for Ukon. When spreading it ressembles a bacterial infection.

When the second level of their seals are active, they resemble ogres with red skin, longer hair, a single horn (on opposite sides for each brother). Also as said by Ukon, can he, while in level 2, deconstruct his body on a molecular level and enter another persons body. At that point he is able to alter the cells and proteins of his target at will, effeciently killing them, and then leaving them to reconstruct his own body again. This technique however has the disadvantage of him taking the same damage as the body he has invaded, as seen when Kiba stabbed himself in the stomach with a Kunai.

However this abillity also allows them to regenerate faster, thought at the cost of a lot of chakra Also while in the second stage of their cursed seal can Sakon and Ukon combine their bodies and which allows them both to act at the same time and have both of their head appear, though it would seem that it is still only Sakon who is in controll.

Also if they are hit by a strong attack they can split up their bodies and grow out their missing arm and leg in the form of an amoured flesh.

An interesting fact is that their Level Two forms are so far the only ones that bare almost no resemble to thei previous forms.

Creation and Conception
Sakon was the final member of the Sound Four to be created by Masashi Kishimoto. After struggling to decide who Sakon should fight, Kishimoto decided to have Sakon take part in a two-on-two battle against Kiba and Akamaru. Thus he created Ukon and placed him within Sakon's body so that they could act as one person.