The 14th, also known as "Pianist" and "Musician," and referred to as the "Noah of Destruction," was a disowned member of the Noah Family and the younger brother of Mana Walker. He was one of the few individuals, alongside Road Kamelot and The Millennium Earl, capable of controlling Noah's Ark. His true name was revealed to be 'Nea,' though it remains unclear if this is his human name or his Noah name.
Thirty-five years ago, Nea attempted to kill the Millennium Earl but failed and was subsequently killed by the Earl. This event has been forgotten by all Noahs except for the Earl and Road, who hasn't reincarnated in 35 years. According to Cross Marian, after Nea's death, Mana lost his mind. However, Nea managed to pass on his "will" to certain individuals, including Cross. Cross later revealed to Allen that he had implanted Nea's memories into Allen to serve as a host for Nea's revival, which would result in Allen losing his identity as Nea took over.
During the Noah's attack on the exorcists' headquarters, Nea's personality temporarily surfaced, revealing his intention to kill the Earl and become the new Earl himself. Prior to his death, Nea was close to the Millennium Earl, having promised to "stay by his side no matter what happens." In the present day, mentions of Nea's betrayal still cause the Earl pain, often bringing him to tears. Despite Nea's plan to usurp the Earl's position, he confessed to the Order that he "wanted to be by the 14th's side."
(Source: D.Gray-man Wikia)
