Kova glided horizontally through the upper reaches of the Void, his disc tilted sideways as he drifted in a slow, lethal circle. He did not look at the ground, yet his single eye remained fixed on the girl who stood amidst the grey smears of his demons.
"You have your beat rhythm," Kova said, his voice echoing from the darkness. "The sound for your second heart has been made. You have broken past your limits, Juno. Now, prepare yourself for absolute pain."
Juno wiped the sweat and dust from her eyes, her chest heaving with every ragged breath. She looked up at the inverted silhouette of the man who was breaking her soul.
"What do you mean beat rhythm?" Juno asked, her voice cracking.
"Focus on what is happening right now!" Kova yelled, his voice suddenly sharp. "Dodge!"
Juno flinched, her instincts screaming, but her body was too slow. She barely had time to register the demon looming behind her.
"What is a socket?" Juno managed to gasp.
The question was cut short as a massive, multi limbed demon slammed a fist into her back. The force of the strike sent her sprawling across the obsidian floor, the air leaving her lungs in a violent burst. She tried to roll, but the pain in her chest was already beginning to shift from a dull ache to a sharp, agonizing pressure.
"The pain will come on day three," Kova remarked, his disc leveling out as he descended. "That is when the socket starts to form. Your body will make a place for the second heart to sit. Do not fight the expansion, Juno. Let the ribs grow.
"The third day arrived with a violent rejection of her own anatomy. Juno did not even have the strength to stand as the first wave of agony hit, a sensation like hot lead being poured directly into her bone marrow. She collapsed, her back arching as her ribs began to groan and multiply. It was not just growth, it was a structural overhaul.
"It is tearing me apart from the inside. My bones are moving, they are breaking and reknitting themselves. I am being hallowed out," Juno thought.
By day four, the pain only intensified as the physical hearts began to shift. The reconstruction was a living nightmare. She felt her original heart being physically dragged across her chest cavity, slid into the first position of the newly formed socket by a force she could not see.
The sensation was sickening, a wet, heavy grinding within her ribs that made her vomit bile onto the obsidian dust.
I can feel my insides moving. Something is sliding under my ribs. I am dying, I have to be dying, Juno thought.
Then, the second heart itself began to cultivate in the second spot. It was not a mass of dark energy, but a physical organ, as crimson and real as the one she was born with. This second heart began to pump with a heavy, unfamiliar rhythm.
"Your second heart is finally forming," Kova remarked, his Void Disc descending as he finally sat upright once more. "Your second heart will be done soon. Get up. Time for rest is over. It is time to resume your training."
By the afternoon of day five, Juno slowly mastered her black flames. Her hands no longer just smoked with dark vapor, but were wreathed in a stable, roaring obsidian fire that did not flicker. It was becoming clear that she was no longer a weakling with her black flame.
The second heart was not even forty percent formed, a raw and unfinished knot of muscle and blood, but it was already beating with a primal force. That half formed pulse was a lifeline, helping her balance the tide of Yen and Yan within her soul. It was the only thing allowing her to overcome the stronger demons that lunged from the dark.
"I feel empty. I dont feel complete, but this pulse is helping me hold on. It is the only reason I am still standing," Juno thought.