Naruto: Reborn as Kakuzu, the Immortal Assassin

Kakuzu glanced at the night sky, its darkness unbroken by even a sliver of moonlight. Slowly, he stood and approached a hidden panel in the floor. With deliberate care, he pulled it open, revealing a staircase leading down into the shadowy depths of a meticulously constructed cellar.

Down below lay his treasure—a secure vault housing the 40 million ryō he had earned over the past six months. Carefully locking the fortune away, he returned upstairs and closed the panel seamlessly. It blended perfectly with the floor, leaving no trace of its presence.

After securing the hidden entrance, Kakuzu's expression changed. His eyes sharpened as a low growl escaped his lips. In a sudden burst of motion, one of his stitched arms shot forward, slicing through the air toward the darkness beyond the window.

"Senju Tobirama!" he roared. "Stop skulking around and show yourself!"

The stillness of the night shattered, and a figure stepped out of the shadows. With a flash, he appeared in the room—silver hair, piercing eyes, and the unmistakable blue armor of the Second Hokage.

"It's been a while, Kakuzu," Tobirama said, his voice calm yet cutting. "Your perception has improved since our last encounter."

"Hmph," Kakuzu snorted. "Spare me the small talk, Tobirama. If you're here to test me again, know this: I've had enough of your games. Tonight, it ends."

He turned fully to face Tobirama, his body taut with tension and his eyes alight with battle lust. Tobirama's presence was a constant irritation—a reminder of the Flying Thunder God mark etched onto his body, a mark Kakuzu had been unable to remove. It was an ever-present vulnerability, one Tobirama seemed intent on exploiting.

Tobirama surveyed the room, his sharp eyes catching the faint traces of Kakuzu's secret.

"So, this is where you keep your earnings," he said casually. "Interesting choice. Though, for someone like me, 40 million ryō isn't exactly a tempting prize."

Kakuzu's fists clenched. "That's beside the point. What gives you the right to come and go as you please? This time it's money—but what if next time, I'm... otherwise occupied? Imagine being interrupted mid... activity by your sudden appearance. Consider yourself lucky I didn't attack on sight."

Tobirama's lips twitched in a smirk. "Is that a challenge?"

"You could say that," Kakuzu growled. "Enough talk. Let's settle this. Here and now."

Tobirama raised an eyebrow. "You want to fight me? Here, in Konoha? That's hardly productive."

"And what's productive, then?" Kakuzu snapped. His arms twitched as the threads beneath his skin flexed, ready to strike at any moment.

Tobirama sighed, crossing his arms. "Your influence in Konoha has grown significantly, Kakuzu. Your monopoly on the glass industry affects nearly every household. It's also driving up costs for my laboratory."

Kakuzu's eyes narrowed. "Ah, so that lab is yours. No wonder you've been tolerating the price hikes."

"Indeed," Tobirama admitted. "But my patience has limits. I came to renegotiate."

Kakuzu pondered for a moment. "Fine. But hear this: if you ever teleport into my home uninvited again, I'll make sure even Hashirama can't save you. Got it?"

"Bold words," Tobirama replied, his tone losing its earlier mirth. "You're not exactly the most trustworthy individual. Do you really expect me to drop my guard?"

"Then send your ANBU to spy on me," Kakuzu snapped. "But if anyone trespasses here without my permission, I'll kill them. Period."

"ANBU?" Tobirama's brow furrowed. "What's that supposed to mean?"

Kakuzu froze, realizing his mistake. Damn it. Konoha was barely six years old—there wasn't even a formal ANBU unit yet.

"Just... you know," Kakuzu said, scrambling to cover. "Shadow operatives. Like assassins. Working in the dark. That sort of thing."

Tobirama's eyes glinted with sudden interest. "Hmm. Shadow operatives, you say? An intriguing idea."

Kakuzu mentally cursed. In his attempt to deflect, he had inadvertently planted the seed for something far more troublesome.

"Enough of that," he said gruffly. "What's your answer on the glass pricing?"

Tobirama smiled faintly. "I'll consider your terms. But don't think this conversation is over. You've given me much to think about."

As Tobirama vanished in a flash of light, Kakuzu slumped into his chair, muttering under his breath. He had only wanted to protect his privacy, but somehow, the encounter had created far bigger problems.

"Next time," he vowed, "I'm installing seals to keep that bastard out."