Here's a possible description for how the protagonist meets the boy and his unusual partner, a pet watch:
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As twilight spilled its golden hues over the bustling streets, she wandered through the market's maze-like alleys. The air smelled of spices and rain-soaked earth, laced with whispers of secrets only the night dared to reveal.
Amid the chaos, her gaze caught a boy sitting cross-legged by a flickering lantern. His face was smudged with dirt, but his eyes gleamed with an unspoken wisdom far beyond his years. He clutched a curious object-a wristwatch that ticked louder than it should have, as if it held a pulse of its own.
The watch turned its tiny face toward her and blinked.
"Don't mind Tik," the boy said with a crooked smile, noticing her startled expression. "He's just a little curious about strangers."
"A watch that... blinks?" she asked, stepping closer.
Tik blinked again, its gears whirring softly. "He's not just a watch," the boy replied, his voice dropping to a conspiratorial whisper. "He's my partner. And it looks like he likes you."
The Black Queen tilted her head, her curiosity piqued. "What are you two doing here?"
"We're looking for someone," the boy said, his smile fading into something more serious. "Someone who might need us. Maybe that's you."
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Does this fit the tone you're imagining? We can refine it further!
What if Rimuru was instead reborn as a primordial demon; the strongest in combat and intelligence.
He reincarnated just before Star king dragon Veldanava created the omniverse; it was nothing but a void, his soul being exposed just a little to turn null made his soul undergo a change. Making him an individual with a high evolutionary potential