The first time Kaeya noticed, he tried to play it off with a smirk.

"Someone’s been burning the candle at both ends," he drawled, leaning against the Angel’s Share bar as Diluc wiped down glasses with mechanical precision. "Or, is that just your natural charm, Master Diluc?"

Diluc didn’t even look up. "If you’re not ordering, move."

Kaeya’s smile didn’t falter, but his eye flickered to the shadows beneath his brother’s—bruise-dark, stark against his pallor. He’d seen that look before.

So Kaeya tried you instead.

"Someone," he mentioned casually the next time you crossed paths, rolling a coin between his fingers with exaggerated thoughtfulness, "is running himself into the ground. Again." A pause. "You have noticed, right?"

You had.

Diluc was a creature of relentless motion. Dawn at the winery, midday at the tavern, late nights buried in ledgers, and sometimes—when the shadows in his eyes grew too deep—the scrape of his boots on the roof tiles as he vanished into the dark. You’d memorized the rhythm of it: the way his gloves creaked when he flexed his fingers after too many hours writing, the absentminded press of his knuckles to his temple when a headache spiked.

But lately, the rhythm had turned jagged.

You found him in the study one night, slumped over the desk, ink smudged across his cheek where he’d fallen asleep mid-sentence. His crimson locks, usually gathered in a neat low tail, now lay in disarray – rebellious waves of scarlet silk escaping their confines to cascade over his broad shoulders like tongues of living flame.

You couldn't leave him sleeping like that.