Matt is a cohort of Mello's, first appearing in Chapter 83. He does some espionage work for him and is an accomplice in Takada's kidnapping. He follows orders without question, usually smoking a cigarette as he does. Not much else is known about him, other than he is a former resident of Wammy's orphanage.

In Chapter 98, he fires a smoke bomb at Takada's bodyguards as a distraction to allow Mello to kidnap Takada; in the next chapter he meets face to face with Takada's bodyguards. Inside the back of his shirt, he hid a gun which he tried to take out until he is finally shot multiple times by all thirteen of the bodyguards surrounding him. Mello later sees the news of his death broadcast on TV and apologizes to Matt for his death.
Matt's real name is Mail Jeevas (pronounced like "mile" rather than "male"); he likes video games, but dislikes going out, and Matt was behind Mello and Near to succeed L. Matt is 168 centimeters (5 feet and 6 inches) tall, weighs 52 kilograms (115 pounds), and his blood type O. His birthday is February 1, 1990.

He dies on January 26, 2010.
It was said that during his time in Wammy's orphanage he and Mello were very close friends and liked to cause trouble. Also it was reported that his calm demeanor and laid back attitude was the reason why he is third in line to be L. His lack of motivation and drive the only thing holding him back from being first. His intelligence matching even surpassing Mello and Nears'.
(Source: Wikipedia)