Near, Mello, and Matt~

Real Names~
Near- Nate Rivers
Mello- Mihael Kheel
Matt- Mail Jeevas

Near
A calm and stoic character that appears in the second half of the series. He subtly represents an albino-like figure with his white hair, and plain white clothes. In the anime and manga versions, Near is a primary candidate to become L's successor and calls himself N during the course of his investigations. He shares a number of similarities with L. Much like how L plays with things such as sugar cubes and forks, Near is frequently shown playing with toys or his hair, and he is constantly shown sitting in an unusual manner. Also, like L, Near likes to stack objects such as dice, while L likes to stack sugar cubes. If you compare the two, you can see they bear some resemblance in appearance as well. After L's death, he was asked to join forces with Mello, who refused (it is explained that Near lacks the emotional insight to beat L, while Mello is too emotional and impulsive). In the manga, Near accepts the fact neither Mello or himself can surpass L, saying that perhaps he lacked dynamics while Mello lacked composure. Near then gained the support of the Government of the United States and formed the Special Provision for Kira (SPK). In the 'extra' manga story, set after the end of the series, Near states that, while he respects Light's drive for justice, he can never find his 'Kira' actions excusable. His real name is Nate River. In the film L: Change the World L gives the name "Near" to a Thai boy who is a mathematical genius; L intends for Near to succeed him.

 Mello

Mello, a character present in the anime and manga versions, was an orphan who grew up with Near and Matt in Wammy's House, Watari's shelter for "gifted" children. Like Near and Matt, Mello was one of the candidates to become L's successor. Similar to L's fondness for sweets, he is often seen eating bars of chocolate. Although Mello is quite intelligent, he often lets his emotions get the better of him. His goal in life is to surpass L and Near. Mello was also killed by minor character Takada Kiyomi. The light novel "Death Note Another Note: The Los Angeles BB Murder Cases" is written out of his view. His real name is Mihael Keehl.

Matt (マット Matto), whose real name is Mail Jeevas (マイル・ジーヴァス Mairu Jīvasu), is a cohort of Mello's. A character in the manga and anime versions, Matt was also a former resident of Wammy's orphanage; Ohba described him as the "third most talented member" of the house. Matt is Mello's helper as Matt performs espionage work and acts as an accomplice in Takada's kidnapping, which results in his death when he is shot by Takada's bodyguards. He is voiced by Tomohiro Nishimura in the Japanese anime and by Drew Nelson in English dub.
According to How to Read, Matt enjoys video games and is not outgoing. He also seems to be a chain smoker. He uses his last breath to smoke his cigarette. He is also directly behind Near and Mello in succeeding L.
Ohba said that he created Matt because when Mello started to act alone Ohba believed that he would find difficulty in advancing the story unless Mello had a character to interact with. Ohba said that to a reader Matt may appear to play video games and have no other actions, but he said that Matt's existence was "important" in the story. In response to a question inquiring about which characters the creators had the most difficulty creating, Ohba cited Matt and said "I didn't even know what kind of person he was!"
Obata said that he did not receive advance notice regarding Matt, who had the character concept of "a young man who loves gaming and doesn't really care much about the world." Obata said that he remembered seeing the thumbnails and asking his editor "Who's this character?!" The thumbnails gave Matt a bowl haircut and goggles; Obata instead drew "what I liked." Obata added that he could "create Matt naturally" as he had a "he probably won't do much" mentality regarding characters introduced in the Near and Mello arc. His birthday is February 1, 1990