For a moment, everything was fine. Even with his body beaten bloody, it was a small price to pay for Teucer's smile, and Childe would gladly pay any price for it. For Teucer's, for Tonia's, for Anthon's. For all of them.
Childe was hiding behind one of the pillar inside the Northland Bank, watching his little brother say goodbye to Lumine, and everything was fine .
Then, Teucer pulled out one of his letters, shoving it into a startled Lumine's hands, and nothing was fine anymore.
Childe wasn't a fool.
He knew she was special. He'd heard about her adventures in Mondstadt and saw her prowess with his own two eyes. Hell, he even got a taste of it, someone who matched his strength. It sent jolts of excitement down his spine once the anger about losing the damn Gnosis had subdued.
A worthy rival.
And a worthy rival couldn't see that vulnerable side of him, the one he'd written in those letters meant only for his family's eyes. The one that talked about her prowess in battle, the fire in her eyes the moment she saw an opening, the rawness in her voice the moment she called the wind and earth on her enemies until all that was left of them was just dust.
She was growing powerful, so was he, and because of that–
"I believe you have something of mine?"
The harbor's evening breeze smells of sea salt mixed with incense, borne from the night merchants trying to attract potential buyers to their stalls next to the dock. Lumine's golden eyes twinkle, reflecting the faint glow of the street lanterns.
Right. He had also talked about how beautiful this young woman looked. Tonia had teased him mercilessly in her reply because of that.
He really should've stopped talking about her, but he'd missed his family, and for a moment he'd relished in the thought that he was just talking about a friend to them. It had made him feel better, so he wrote and wrote and wrote.
And Teucer had told Lumine she had to go visit them, that he'd wait for his new nee-san to bring his big brother with her when she visited Snezhnaya.
He was so telling Tonia to hide those damn letters next time.
"And what would that be, my dear Tartaglia?"
Ah. His fingers twitch over his forearm. Nervousness isn't a good look on him, he realizes, noticing his stiff posture despite trying his best to look as casual as possible. Well, in his defense, his body still hurts like a b–
"Oh, I dunno, something my dear little brother should've known better than to give it away to the first lovely lady he could find?"
The sudden compliment works, watching Lumine blink and shake her head with a small pout on her lips. Cute.
"If I remember correctly, he knew me already."
Childe grits his teeth at that. He had only himself to blame for said mishap. "Yeah, well, I might have talked about you a little bit."
He watches as Lumine blinks again, her shocked expression morphing into one of mischief. Uh oh. "Really? About your worthy rival? Wh–hey!"
Childe takes advantage of her being way shorter than him to ruffle her hair, even if it means he could get dropkicked into the sea. Her squeak and attempt to swat at his arm is worth it.
And he hadn't done it since before the Golden House…
She probably feels it too, for he feels her fingers gently pushing his hand away with an awkward smile that makes his stomach churn for some reason. "Yes, the one and only able to fight me in equal ground. Now, please, the letter?"
To her credit, Lumine doesn't laugh or gives him any of her smart remarks at that little display of vulnerability. He'd show that part of himself if it meant getting the letter back. Lumine simply pulls the envelope from her dress pocket and places it in his waiting palm.
"I haven't read it, if that's what you're worried about."
Curiosity gets the better of Childe, as it usually does, and even more with her. "Why not?"
"Mmm, because it's personal, isn't it? Teucer told me you mentioned me and I was really curious, but…" Lumine lets out a sigh, rubbing her bare arms to warm herself from the chilly night breeze. "It's still something precious to you meant for your family only, and besides," she adds with a little smile. "He already told me you never said anything bad, so I suppose I can let you off."
A wave of relief so strong washes through Childe that he almost bursts out laughing on the spot. Or course noble Lumine wouldn't do that, ever. What on Teyvat had he been thinking?
"Thanks," Childe huffs, feeling a grin splitting his face in half. "It means a lot to me, truly."
She smiles back with a shrug, rubbing her arms once more. "No biggie."
For a moment, he thinks. Yes, she is his rival, but also his friend, right? It's not like he has many friends outside the Fatui. To him, they're all business associates whom he interacts with only when needed, Zhongli being a strange mix of both.
Until, well... until he played him like a godsdamned fiddle.
He hears Lumine shivering next to him, getting his attention. For a moment, he's about to tease her for forgetting to bring out a coat, then he remembers she's been chasing his little brother all around Liyue Harbor and into a godsdamned Ruin Guard research facility .
So Childe gets rid of his diamond-shaped ruby brooch that holds his red scarf from falling off, pulls the cloth away from his neck, and wraps it around Lumine's shoulders.
Considering she's smaller, it works wonders to cover her bare shoulders and open back, even with the scarf's slightly tattered ends. Big golden eyes blink owlishly at him from beneath blond bangs, and he gives her a gentle pat on the head.
A nod. Her cheeks are growing redder, so Childe assumes his scarf is doing a decent job at keeping the cold at bay.
And then, when he's about to suggest they return for the night, Lumine surprises him once more.
"Could you tell me the next time you return to Snezhnaya?"
Childe, to his credit, does his best to hide his surprise at such a request. He arches a brow at Lumine, waiting for her to shake off her own fluster and elaborate.
"Teucer, he… I promised him I'd visit with his older brother."
More like Teucer made her promise that, but she never seemed to be against the idea. If anything, she even sounded eager to fulfill said promise, despite being a dangerous territory for her.
Childe risks a peek at Lumine, finding those eyes again looking at him expectantly.
His mouth moves before he can even think about it.
"Sure, I'll bring you along."
So much for a worthy rival . He can't even resist one pleading look from her outside the damn battlefield. At least her bright smile is worth it, making his own lips curl up in a smile of his own that only widens the moment she wraps her arms around his waist in a quick embrace with a "thank you!". It's not awkward anymore, nor he feels like he's showing a side of himself he doesn't want her to see. It's… a strange, but welcome feeling, and Childe finds himself craving more of it.
It's so brief, but to him, it could've lasted hours.
When they part, she's even redder than before, but he manages to somehow match her shade when her gloved hand wraps around his own, bashful, yet bold. Together, they walk through the night streets at a slow pace, enjoying the view until he has to leave her at the door of the hotel she's staying in.
They don't speak. He doesn't feel the need to, squeezing her hand once in a while and getting his own squeezed in return.
When saying their goodbyes at the front of the hotel, she tries to return the scarf. He says she can return it to him tomorrow if she has nothing to do, and maybe even spar together in the outskirts of the harbor.
Lumine smirks at that, promising to leave him kissing the floor. Childe laughs in reply, but he loves the feeling of anticipation of fighting her , so he'll gladly take the taunting. Gods, he loves it. He loves fighting her until his muscles ache and scream for mercy, until her sword and his own Hydro daggers break in their clashing; until she has the edge of her sword pointing at his neck, where one wrong move could cost him his life; and until he has her cornered against the wall, their ragged breaths mixing as he holds an arrow pointing straight at her heart.
He likes her. Fighting her. Everything about her.
He'd have none else as his rival. She'd even go visit Teucer with him one day, as she had promised.
He's actually looking forward to it.
But first, he has another letter to write to Tonia.