Flames of White
Karasu stayed upon the mountain that the dragon within him had sent him to for three long years, training his control over the power within him. As he sat in meditation atop the mountain's peak, he was overcome with the feeling that his father had passed. Karasu focused on that strange sense of emptiness, feeling the veins around his eyes rise as his mind's eye seemed to fly across the land. He let out a shuddering gasp as his mind's eye came to a halt, showing him his father and uncle atop an old building. His father lay dead on the ground, the sickness he had tried to hide for so long finally claiming his life. Sasuke stood beside his brother, a strange figure hovering in the air above him as black flames covered the building's roof.
Something was off about the hovering figure, his form seeming to waver through Karasu's sight. He felt he should know this person, that their paths had to have crossed at some point already. Karasu watched as the mysterious figure vanished in a wavering swirl, as though passing through some rift in space. He saw Sasuke's chakra become a dangerous shade of red as he screamed his anger and pain into the sky, unheard by the mysterious figure that had been there only a moment before.
Karasu opened his eyes and gasped, his vision still focused on a point far, far away from where he now sat. A sharp pain erupted in his eyes, causing him to fall over in the dirt as he cried out and held his hands against them. He noticed something different in the texture of his face around his eyes, gently running his fingers along the raised ridges as the pain subsided. He crawled to a pool of water that he gathered within a depression in one of the boulders nearby, his breath leaving him as he beheld his eyes; he had awakened his Byakugan, but it wasn't like his mother's.
Karasu blinked as he beheld the trio of crimson tomoe within his eyes. He knew that his Sharingan's tomoe were not the black of the other Uchiha, but he had never seen any kind of tomoe in his mother's eyes. He vaguely recalled his mother explaining that the Byakugan left the eyes devoid of any color, a fact that continued to mystify him as he beheld the difference between his eyes and hers.
The Byakugan you possess is purer than that of current generations. He heard a voice whisper within his mind, a voice that he had not heard before.
"And what might you be?" Karasu asked the new entity.
I am the source of what your mother's people call the Byakugan, the first being to possess it. The voice whispered in response. Karasu was beginning to feel that his connection with this entity was weaker than his one with the black dragon, as its voice wasn't as clear.
You have only begun to awaken my power. You will bond with me as you use my power more. It said, answering his thoughts.
"Are you a dragon as well?' He asked, though he didn't get a response.
That was the White Dragon Emperor. Your mother's ancestors called it Shiro, just as your father's ancestors called me Koku. The black dragon said from within him.
"So your name is Koku. Nice to finally put a name to your voice," Karasu said sarcastically, annoyed that he had spent three years in isolation with the black dragon and was just now discovering its name. Koku chuckled within him.
Shiro's power requires a more fine-tuned control than my own. While my power is meant to lay waste to everything in sight, Shiro's is meant to be focused into a much smaller point. It was he that first taught the Hyuga the fighting style they now use. Koku explained.
"I see," Karasu said.
Karasu found it harder to maintain control over his grief as Koku continued to drone on about the dragons' history, kneeling in the dirt and letting his tears flow freely as his body rocked with violent sobs. Koku went silent as he realized that Karasu was overcome by his grief, not knowing how to soothe the young boy.
White flames began to form a circle around Karasu's body, wispy tendrils reaching up to gently caress and embrace him. He heard his mother's voice faintly within the flames, singing the cradle song she had sung to him nearly every night when she was alive. His sobs became more violent, slowly fading as the sound of his mother's voice calmed him. He fell asleep where he lay atop the mountain, his last conscious thought being of his parents.