Before facing her master, Kuroka headed towards the laboratories to eliminate possible threats that would interfere with his fight with his master. She entered the place with fury in her eyes, and mercilessly attacked all the demons who were scientists and guards of the place.
With agile movements, Kuroka attacked with sharp claws and senjutsu skills, taking down his enemies one by one. She looked almost unstoppable, like a force of nature, and her fury ended up scaring her younger sister who was hiding watching from afar.
As Kuroka advanced deeper through the lab's corridors, killing all the researchers and guards she found in her path, she finally reached a corridor where one of the lead researchers was cornered. The man was shaking in fear as Kuroka slowly approached, her claws wrapped in demonic energy.
"Please do not kill me!" implored the researcher, his hands shaking as he tried to shield himself from the impending attack. "I do not want to die!"
Kuroka just looked at him coldly, not showing any compassion. She knew that man was one of those responsible for torturing and experimenting on demons, including herself and would possibly do the same to her younger sister.
"You deserve death, just like everyone else who works in this accursed place," Kuroka said in a low, menacing voice. "There's nothing you can do to change that."
The researcher continued to plead for his life, but Kuroka showed no mercy. She lunged forward and dealt a lethal blow with her claws imbued with black flames, slitting the man's throat and killing him instantly.
Shirone, who was hiding in a corner of the hall, watched in horror as her sister killed the researcher without hesitation. She had never seen Kuroka act this way before and was completely shocked by the brutality of his actions.
As Kuroka walked away, Shirone remained frozen in place, unable to move or speak. She couldn't understand how her sister, the person who had always protected her, could be so cruel and violent. The shock of that experience would change the way Shirone saw the world from now on.
Using her youjutsu, she generated illusions in the form of her clones, confusing the demons that tried to attack her. Furthermore, Kuroka cast a poisonous mist in the areas she passed, causing chaos and confusion among his enemies.
The demons tried to fight back, but Kuroka's skill and handling of demonic energy seemed to be superior. She was determined to end the transcendental demon project and free the demons that were being used as guinea pigs.
However, when she reached the testing area of the deeper laboratory, she found none of the Naberius experiments she was used to, but some even more violent and disgusting than what she had already witnessed in the past.
Upon entering the test area of the Naberius family laboratories, Kuroka was faced with a terrifying scene. The walls and floor were covered in blood and shredded flesh, evidence of the brutality that had taken place there. The bodies of several demons were strewn around, some dismembered, some with exposed internal organs, and still others with marks of torture all over their bodies. Kuroka felt a mixture of anger, fear and sadness as she saw the scene in front of her.
She walked cautiously through the halls, trying not to make any noise and to remain invisible. Meanwhile, she used her senjutsu to detect possible threats. She knew there was something wrong there, something much bigger than just the Naberius family abusing the power they held over low-class devils.
Upon arriving at the experiment room, Kuroka found something even more shocking. Several cages were scattered around the room, each containing a different demon. Some of them appeared to be sleeping, while others appeared to be in agony, trapped in chains that were squeezing their bodies. Kuroka could see that the cages had a ventilation system that was being used to release a poisonous mist into the environment.
Meanwhile, a group of Naberius family guards had arrived at the experiment room as they searched for traces of Kuroka amidst the killing he was causing. They spotted Kuroka and immediately tried to capture her, but she was faster and disappeared in a puff of smoke.
Using her youjutsu skill, Kuroka created several illusions of herself and began to move quickly around the room, dodging the guards and traps that were scattered around the room. She eliminated the guards and then decided to give a coup de grace to each of the devils who were trapped serving as guinea pigs for inhuman tests and who begged her to kill them and make the pain stop.
In the end, Kuroka emerged victorious from the fighting inside the Naberius family's laboratories, with her enemies dead at her feet. But, even with the victory, she knew that her battle was not over yet, and that facing her former master would be the hardest fight of her life and this fight was about to start when a man with a familiar face came walking slowly towards her with an expression of pure hatred.