Raxhyr was born after Harry Potter released his own heart with the Keyblade.
Due to the fear that Harry Potter had about having his inner darkness taking hold of him, he decided to release his heart, freeing himself from said darkness. As a result, Harry Potter faded into nothingness, and with his heart consumed by the darkness, his body and soul were reborn in Twilight Town as a Nobody.
After awakening, Harry's Nobody was approached by a cloaked man, later revealed to be Xemnas, who invited the newborn Nobody to join the Organization. As he accepted, Xemnas preformed the naming ceremony, granting Harry's Nobody the name of Raxhyr. Xemnas then brought Raxhyr to The World That Never Was, where Raxhyr was introduced to the other members of the Organization.
As he joined the Organization, Raxhyr began to recover the memories of his original self. His first mission had been with Marluxia, where he learned that his objective was to collect Hearts using the Keyblade, releasing them from the Emblem Heartless. The following days were spent with Raxhyr going on training missions with other members of the Organization, learning more about their ultimate goal of completing Kingdom Hearts. Eventually, he was deemed ready for official missions by Saix, being paired with Xaldin for said task.
Much like the other Organization members, Raxhyr possesses no emotions, relying only on the memories of his Somebody to emulate the very emotions he lacks. He seems to hold a certain level of disdain towards his Somebody, to the point where he attempts to act in a more serious and thoughtful manner, unlike his original self.