Yayap

Yayap was a Covenant Grunt in the Fleet of Particular Justice. He later became SpecOps Elite Zuka 'Zamamee's assistant.

Yayap was born on the methane filled Grunt home world, to which he continually dreams about returning. Yayap was a red armored Grunt assigned to a sleepy Grunt unit, commanding others of his race, including Gagaw. However, during the boarding of the Pillar of Autumn, a black-armored Special Ops Elites named Zuka 'Zamamee was incapacitated by a bullet shot by the Master Chief. Yayap and his team of Grunts found him still alive and decided to bring him back to the boarding ships; this would allow them to escape the fighting on board the Autumn. After Zuka 'Zamamee regained consciousness, he decided to have Yayap transferred to be his personal aide; his own was killed in the fight aboard the Pillar of Autumn. Yayap was understandably less than elated at this piece of news: Elites are notorious for not caring about their lives or those placed under their charge.

NOTE: At this point it is assumed that Yayap becomes one of the Special Ops Grunts.

Zuka 'Zamamee then goes before a small council situated on Halo to request permission to kill the specially armored human (Master Chief) who was solely responsible for scores of Covenant casualties; he is refused. However, after a boarding assault on the Truth and Reconciliation retrieves Captain Jacob Keyes and takes out several hundred Covenant warriors, his request is reconsidered and granted.

Yayap then follows 'Zamamee to the security center of The Silent Cartographer where he attempts to kill the Chief using a pair of Hunters and some Grunts under Yayap's command. However, one of the Grunts, named Linglin, accidentally kills one of the Hunters, allowing the Chief to overcome the force. Yayap narrowly avoids being killed when 'Zamamee pulls him into a cargo pod.

He is then used as the bait for 'Zamamee's next plan. He is beaten up and laid out next to a crashed Ghost on a path where the human insurgents will find him, carrying a few Memory Blocks and some food to ensure he will not be killed by humans. He is then captured by First Lieutenant Melissa McKay and, unbeknownst to her, carries a transmitter that he activates once he sees the Chief, allowing 'Zamamee and Noga 'Putumee to land forces at Alpha Base. The attack is a failure, and he is freed and escapes with 'Zamamee aboard a Banshee, actually pointing a Plasma Pistol at the Elite's head so as to convince him to retreat.

They then travel to the Pillar of Autumn crash site so that Yayap can get a supply of methane. They assign him to inspect cargo and command a group of Jackals. At first, the Jackals are disgusted of being under his command, calling him a "gas sucker" but their minds changed after Bok is killed by a group of Flood that were contained thanks to Yayap's vigilance. Yayap the Grunt was elevated, in their eyes, to honorary Jackal.

He is finally assigned to monitor communications for 'Zamamee when the Chief is detected aboard the ship. He knows that 'Zamamee will not win a battle against the Spartan, so he abandons the Covenant forces and escapes on a Ghost, hoping to join a few other deserters and live on what is left of his methane reserves in freedom.

He is supposedly killed in the explosion of the Autumn's fusion engines that obliterates Installation 04. His fate is unknown, and he may still be alive, somehow. As First Strike indicated, Cortana's first few searches only picked up "Dust and Echoes," but eventually, survivors of Halo's explosion were found. It is still possible that Yayap is still alive, but the chances are very slim.

Trivia
In Halo 3, one of the outcries by other Grunts when a Grunt is killed is "You killed Yayap!" This may be a joke or it's possible that "Yayap" is a common Grunt name. Also may be a play on the frequently repeated quote from South Park, "You Killed Kenny!"
 * In Contact Harvest it is mentioned that Bapap is Yayap's cousin.