Manda

was the personal summon of Orochimaru.

Personality
Manda was very snobbish and prideful, believing himself superior to everyone. He apparently only served Orochimaru because he could not successfully defeat him, as Kabuto expresses concern that Manda would turn on them if he knew Orochimaru couldn't perform jutsu. Even in this instance, he complains about the conditions he is summoned into and demanded that he be given a hundred human sacrifices as compensation for his help. When they lost this battle, Manda threatened Orochimaru to be prepared for a punishment during their next encounter. Manda had mutual animosity for Gamabunta.

Search For Tsunade arc
Orochimaru (with Kabuto's assistance) summons Manda to combat Tsunade's Katsuyu and Jiraiya's Gamabunta. After relishing in the possibility of getting to eat the other two summons, Manda attacks. He tries to constrict Katsuyu to death, but she divides herself to escape. Jiraiya and Gamabunta then try to catch him in a firestorm, but he burrows underground to sneak up on them. Before he can land an attack, Tsunade drives Gamabunta's sword through the roof of his mouth, pinning him down and leaving him unable to eat anyone. Angered by the humiliation, he threatens Orochimaru before leaving.

Hunt for Uchiha arc
Nearing the end of their battle, Deidara was forced to use his ultimate technique (self destruction), as a last resort to kill Sasuke Uchiha. Relying on quick thinking, Sasuke summoned Manda and used his Sharingan to control Manda with a genjutsu. Sasuke hid within his mouth, escaping Deidara's final blast. As a result, Manda had taken nearly all of the damage, thus inevitably leading to his death.

Abilities
Manda was very powerful, and able to stand his own against Gamabunta and Katsuyu and had almost killed them both before being disabled. He was extremely fast, as he was quickly able to dodge and disable Katsuyu. It's also obvious that he was well known, as Gamakichi is afraid of him just because of his gaze. He was also able to shed his skin in a manner similar to the Body Replacement Technique, which is seen during the battle with Gamabunta and Katsuyu, and to move underground.

Trivia

 * According to Suigetsu, Manda was Orochimaru's first pet.
 * Manda's mouth appears to not have a tongue.