In the forest behind the mountain, the night wind was bleak and the shadows of the trees swayed, yet they were almost frozen by the terrifying pressure between the two.
Arisu floated in midair, his plain white robe fluttering. His indifferent eyes, almost devoid of emotion, stared at Yumeko below.
Yumeko also unleashed the combined power of Indra and Asura to resist Arisu.
But this resistance was undoubtedly insignificant.
"You think this lowly trick can make me hesitate to act?", Arisu said coldly.
Yumeko endured the pressure that almost seemed capable of crushing her soul. Yet she still kept that smile on her face.
She knew this was the only trump card she currently had. If the Observer disregarded everything and killed her, it would really be over.
"Lord Observer, you and I both know how important Black Zetsu is to the entire plot."
"It's one of the 'causal lines' you personally pushed forward, isn't it? If it dies now... Kaguya's resurrection, Uchiha Madara's Infinite Tsukuyomi, and even the entire subsequent Fourth Great Ninja War will all develop uncontrollable deviations. You should be even less willing than I am to see that kind of situation get out of control.", Yumeko spoke in a trembling voice.
Arisu's brows furrowed slightly, and an extremely faint ripple flashed through his eyes.
Yumeko's system was special.
That kind of system binding was not a simple contract, but a connection almost like a link between the origins of their lives. If Yumeko were killed, there was a high chance Black Zetsu would also disappear.
Anything produced by the system was bound to be high quality.
Seeing that he remained silent, Yumeko grew a little bolder and continued, "I really have kept our agreement all these years and never actively interfered with the fate of Indra and Asura."
"I just... want to survive. You promised me back then that you would let me live until the Fourth Great Ninja War. Now you suddenly want to kill me. Isn't that a little dishonest?"
Arisu slowly raised his palm and pointed it at Yumeko.
"Dishonest?"
"You used the system to bind Black Zetsu, seriously disrupting the established course. The original 'observation' has already developed a crack... What I hate most is the appearance of uncontrollable variables."
BOOM!!!!
The terrifying pressure surged once again. Yumeko's legs went weak, and she nearly fell to her knees.
She gritted her teeth, cold sweat streaming down her forehead, yet she continued staring firmly at Arisu.
"My lord... Killing me is easy, but what happens after Black Zetsu dies? Are you going to create a new 'Black Zetsu'? Wait another few hundred years?"
"Or are you willing to personally fill this enormous gap in the causal line?", Yumeko hurriedly spoke.
Arisu fell silent.
Time seemed to stretch on and on at that moment.
Arisu thought for a while. Was he supposed to play the role of Black Zetsu himself?
He couldn't put himself into that role.
He had lived for too many years, and his personality had changed greatly as well.
Yumeko nervously watched Arisu, drenched in sweat.
She knew that an existence like the Observer would never compromise simply because he was threatened.
The Observer was only weighing things, considering which was smaller, the cost of killing her or the risk of letting her go.
After a while, the black radiance in Arisu's palm gradually faded.
Arisu looked down at Yumeko from above. There was not the slightest trace of warmth on his handsome, cold face, but he finally spoke.
"...Very well."
Yumeko was ecstatic inside, but she didn't dare show it too clearly. She only breathed a little easier.
Arisu's figure slowly descended a little, his gaze scraping across her face like a blade.
"But I won't let you continue acting without restraint. You can keep Black Zetsu as this new host, but everything it does must strictly follow the original script. No deviations are allowed."
Yumeko hesitated for a moment before finally nodding, "...I promise."
Arisu sneered, "Promise? Your promise is now worthless to me."
"I'll keep an eye on you from the shadows."
"As soon as you make one move beyond what I can tolerate... even if Black Zetsu dies, I will personally erase you from this world completely."
"Remember, I have plenty of ways to make the 'causal line' converge again.", Arisu said coldly.
Yumeko's heart tightened, and she lowered her head.
"Yes, I understand."
"Listen carefully, Yumeko. From today onward, you'd better keep your head down and behave."
"Don't cause trouble for no reason, and even less so try to challenge my bottom line."
"You can keep Black Zetsu, but every one of its actions must strictly follow the original course. If I discover that you're secretly using the system to make little moves, trying to change the greater course of events, or if you dare use Black Zetsu as a shield to threaten me again..."
Arisu paused, and his voice suddenly became low and cruel, "I'll make you understand what it means to be unable to live or die in peace."
"I have countless ways to make your life worse than death while still keeping you alive."
Arisu's tone was chilling.
Yumeko's face instantly went pale, cold sweat rolling down her forehead.
"I... I understand. I won't act recklessly again.", Yumeko's voice trembled slightly.
Seeing her submit, there was no satisfaction in Arisu's eyes.
"Actually, you don't need to feel too pleased with yourself."
"This world has already gone through countless cycles. The grudge between Indra and Asura, the inheritance of the Sage of Six Paths, Kaguya's resurrection, Uchiha Madara's ambition... All of these things have played out hundreds or thousands of times."
"With every cycle, the details may be slightly different, but the final direction always leads to the same destination."
"And you, Yumeko, are merely one insignificant occurrence among these countless cycles. A transmigrator with a system, thinking she can stir up some kind of storm?"
"In my eyes, you're no different from those self-important 'protagonists' and 'transmigrators' before you. In the end, you're all just a speck of dust in the long river of causality."
Arisu gave her one last deep look.
"Get lost. Take your new toy and get as far away as possible. Don't let me see you again at any of these critical points in the future."
As his voice fell, Arisu's figure gradually faded like smoke, eventually disappearing completely into the night.
Only a deathly silence remained in the forest behind the mountain.
Yumeko's legs went weak, and she collapsed directly onto the ground, gasping for breath.
Cold sweat had already soaked through the back of her clothes, and her heart was still pounding wildly.
"...I survived.", She murmured to herself. There was relief in her eyes at having escaped the ordeal, along with deep wariness.
At the same time, deep beneath the earth, Black Zetsu's mass of black shadow slowly gathered, its green eyes filled with uncertainty.
"This woman... just what is her background?"
Black Zetsu couldn't help feeling a little overwhelmed. 'Could she really be a transmigrator?'
———
In the distant Ninshu, the battle between Indra and Asura was still continuing, the sounds of their chakra colliding rising and falling one after another.
The fate of the two brothers, destined to turn against each other, had not changed much because of tonight's little incident.