Crossover System: That Time I Got Reincarnated As A Narsisitic Human

The journey down the mountain had turned out to be more challenging than Shiro anticipated—not because of the terrain, but because of the constant nagging thought in the back of his head. 'Money. Shelter. Food. Kids. Money. Shelter. Food. Kids. ' The cycle was endless. But despite the creeping anxiety, his enthusiasm never wavered. After all, a good leader—nay, a great leader—never let their followers see them sweat.

"Alright, you two," Shiro declared, hands on his hips as they took a short break on the side of the winding mountain path. "It's time for your first lesson in Curse Energy 101, taught by yours truly, a certified genius. Get ready to be amazed!"

Nanako and Mimiko, sat on a big rock, tilted their heads in unison, their timid eyes filled with curiosity.

"Now," Shiro began, pacing in front of them like an overenthusiastic professor. "Curse Energy flows through your body like—oh, how do I put this in a way you'd understand? Ah! It's like the batter in a pancake. You want it smooth, no lumps, and perfectly spread out."

The girls exchanged a confused glance.

"No, no, wait," Shiro said, stopping mid-pace. "Bad example. Think of it like… a river! Yeah, a river that flows with control precision, destination and power. Except sometimes the river floods, and that's where you need control. Got it?"

Nanako blinked. "A… pancake river?"

Mimiko tilted her head. "Do rivers… have pancakes?"

Shiro froze, his expression unreadable. Then, with a theatrical sigh, he waved them off. "Alright, scratch that analogy. Clearly, you're not ready for my advanced metaphors. Let's just skip to the fun part. Focus on your energy, feel it moving through your body, and try not to blow anything up. Easy."

Nanako and Mimiko nodded hesitantly, closing their eyes and attempting to follow his instructions.

The two girls had already awakened their Innate Curse Techniques—much to Shiro's jealousy.

"Kids these days," he muttered under his breath, arms crossed as he watched them try to control their energy. "Born with all the cheat codes. Meanwhile, I had to grind my way to greatness."

The girls didn't notice his grumbling. They were too busy furrowing their brows in concentration, trying to tap into their energy as Shiro had instructed.

After a few minutes, Mimiko opened one eye. "I… don't feel anything."

Nanako frowned. "Me neither."

Shiro groaned, pinching the bridge of his nose like a man burdened with the weight of genius. "No, its ok. You can take it slowly. You're just… not me. Which is fine! Totally fine! Not everyone can be this amazing as me. It's a high bar. I'm just built different."

Nanako and Mimiko exchanged a look, realization dawning on their faces. Their big brother wasn't just eccentric—he was also a massive narcissist.

But instead of being annoyed, they found themselves smiling quietly. His self-absorbed remarks were oddly endearing, a unique mix of absurdity and confidence that kept their minds off the harshness of reality.

"Alright," Shiro continued, snapping his fingers. "Let's take a break from all this 'curse control' stuff. Your brains are clearly not ready for my level of insight. Don't worry—I'll dumb it down for you later."

He sat down cross-legged across from the girls, then, with a quick flick of his hand, opened the [Shop] from his [Crossover System].

"Alright, kiddos, time to feast," Shiro declared with a wide grin as an array of food and beverages materialized before them. Three massive hamburgers stacked high with toppings, crispy golden fries, chocolate sundaes drizzled with syrup, and three chilled, sparkling drinks appeared like a banquet fit for royalty.

Nanako and Mimiko gasped softly, their wide eyes sparkling with wonder. "W-where did this come from?" Mimiko asked timidly, her voice barely above a whisper.

Shiro waved a hand dismissively as if conjuring gourmet meals from thin air was the most normal thing in the world. "Magic, obviously. The perks of having me as your big brother."

The girls' eyes lit up as they accepted his explanation without question, their gazes fixed on the food like it was a miracle. Tentatively, they each picked up a burger and took cautious bites.

Their reactions were immediate. Nanako's shyness melted away for a moment as her face lit up with delight. "This… is so good!" she exclaimed softly, her voice carrying a rare note of excitement.

Mimiko nodded enthusiastically, cheeks puffed with fries, her quiet demeanor momentarily replaced by pure joy.

Shiro leaned back against a tree, sipping his drink with a satisfied smirk. "Of course it is. Only the best for my little sisters. And by the way, you're welcome. I won't even charge you for this five-star experience."

The girls giggled quietly, their spirits visibly lifted by the unexpected feast.

As Shiro watched them eat, a fleeting smile crossed his face. Now that food's handled, thanks to the system, money's not as much of an issue anymore. The only problem left is… finding a proper place to live.

He tapped his drink against his knee in thought, his gaze softening as he watched the girls. Their small, malnourished frames seemed so fragile, and the sight reminded him of what could have happened to them.

His jaw tightened. I remember their fate. Sukuna slaughtered them, tossed them aside like they were nothing. But this time… Shiro clenched his fist, determination hardening in his chest. This time, they're with me. That fate won't repeat itself. Not on my watch. Not ever.

He took a deep breath, letting his confidence return as he glanced at Nanako and Mimiko. They were family now—his family—and he wasn't about to let anything happen to them.

He stretched his arms behind his head, his grin returning as he teased, "Don't get used to five-star meals every day, though. Big Brother Shiro has a budget, and it's… let's call it creative."

Nanako tilted her head. "Creative?"

Mimiko swallowed a bite of her sundae. "What's a budget?"

Shiro stifled a laugh, ruffling both their heads. "Don't worry about it, kids. You'll learn all the important stuff when you're older. For now, just enjoy the perks of having the best big brother in the world."

The girls nodded eagerly, their spirits lifted not just by the food but by Shiro's unwavering confidence and humor.

As they finished their meal and prepared to continue their journey, Shiro stood, looking down the winding path ahead. We'll make it to the city soon. I'll figure things out when we get there. For now, I'll just keep being the guy they can rely on.

With a stretch and a flourish, he turned back to the girls. "Alright, little sisters! Let's get moving. The city's waiting for us, and I hear step three—profit—is going to be legendary."

Nanako and Mimiko giggled softly, falling into step behind him as they walked down the mountain together, their trust in Shiro growing stronger with every step.

…

From time to time, their journey down the mountain came to a halt as Shiro insisted they rest whenever the girls looked tired. Their malnourished bodies couldn't handle the pace he could, but he didn't mind at all.

"Break time," he'd announce cheerfully. "Big Brother Shiro decrees it!"

"B-but we can keep going," Nanako protested weakly once, clearly worried about slowing him down.

"Nope," Shiro said, wagging a finger. "Rule number one: no overexerting yourselves. Rule number two: Big Brother Shiro is always right. Now sit."

As they rested during one of their breaks, Nanako finally worked up the courage to ask, "Shiro… what's the city like?"

Shiro's expression softened as he leaned back on his hands, gazing up at the sky with a thoughtful smile. "The city, huh? Well, it's beautiful, for one thing. Tall buildings that scrape the clouds, lights that make the night look like day, and food—oh, the food! Stuff you've never even dreamed of."

The girls' eyes widened in wonder, their imaginations running wild.

"But," Shiro continued, his tone growing more serious, "it's not all sunshine and pancakes. The city has its dark side. There are bad people, selfish people, and plenty of folks who'll try to take advantage of you if you're not careful."

He glanced at them and noticed their confused expressions. Shiro sighed internally. They didn't get it, he thought, watching their innocent faces. He leaned forward, his voice dropping to a gentler tone. "Just think of people far worse than the villagers back there."

The memory of the mistreatment they endured in the village surfaced, and both girls flinched uncontrollably, their small bodies trembling at the thought.

Shiro immediately reached out and ruffled their hair, his grin returning to reassure them. "Hey, don't look so scared. You've already seen the worst of human nature in that awful place. The city? It's just bigger, louder, and a little crazier. But here's the thing—" He leaned in closer, flashing a cocky smile. "You've got me. And no bad guys out there can handle the mighty Shiro."

Nanako and Mimiko looked up at him, their timid expressions softening as they nodded. Their trust in him remained unwavering, like a faint but steady light in their otherwise dark memories.

"Good," Shiro said, standing up and dusting himself off with exaggerated flair. "Now let's get moving. The city's not gonna come to us, and I hear step three—profit—works way better in urban settings."

Mimiko leaned toward Nanako and whispered, "What's profit again?"

Nanako shrugged, frowning slightly. "He still hasn't told us."

Shiro overheard and stifled a laugh, throwing an arm around each of them as they prepared to set off. "Don't worry about it, kids. Stick with me, and you'll learn everything you need to know. Lesson two: always look forward, never back. Unless it's to see how far you've come—that's fine."

The girls nodded again, faint smiles breaking through their timid faces as they fell into step beside him. For all his eccentricities and ridiculousness, Shiro's presence wrapped them in a warm, protective aura. As long as he was with them, the road ahead didn't seem so frightening.