Ever since the first time he had met Kaeya when his dad took him in, Diluc remembered how Kaeya had always been never devoid of nightmares.
Diluc first saw it when he was watching over him that night, holding his cold and shivering hands.
It starts of with a groan from his little mouth and his eyebrows furrowing. What followed is a huge gasp as Kaeya's eye shot open, his sapphire eyes swelling with tears.
“Did you have a nightmare?” an eight year old Diluc had asked, his voice filled with worry, which caught the attention of the other. “I know we just met earlier but Adelinde's busy making food and Dad said he has something to do quickly, so you're kind of stuck with me right now.”
Kaeya had only sniffed even more, now sobbing uncontrollably yet quiet that Diluc can almost feel his panic inside his throat.
Diluc firmly held Kaeya's hand, both of their complexions complementing each other under the light of the candles surrounding their room. The rain still poured heavily outside the manor, and it didn't escape Diluc's sight on how Kaeya had flinched with the sudden sound of the thunder accompanied with the lightning.
“Do you mind if I lay beside you? You know it will probably help the nightmares a little.”
Kaeya only nodded and moved to give him a space to fit beside the bed. Diluc slipped underneath the sheets without removing his hold on the other's hand.
It only took them a few minutes before both had evened out their breathing, falling into a deep slumber.
The next morning, one of the maids had scolded him for laying next to Kaeya with the possibility of accidentally hurting his injuries, but Diluc had thought that it was all worth it when Kaeya told him that it did help with his nightmares.
Within the years that passed, both of them had grown close with each other easily. Kaeya had basked with the warm that Diluc radiates, and Diluc always wanted to have someone whom he can do his best to take care with.
It wasn't also a secret to everyone that every night where Kaeya had nightmares where he couldn't usually handle alone, he would often slip inside Diluc's room who would always welcome with a reassuring smile.
“Had a nightmare again?” Diluc asks, snuggling against the body of Kaeya against his.
Kaeya places his arm around Diluc's waist for an embrace, immediately relaxing as Diluc's scent covers his nose. He hummed as answer, his head tucked under Diluc's chin.
“You're comfy,” he whispered before a yawn.
Diluc smiles, “And so are you.”
He always had treasure those little memories of them, taking each other's warmth, cuddling while asleep, inside his mind. It was something that can never be replaced nor removed even after they and their fallout.
When Diluc came back after his years long journey outside of Mondstadt, he did not expect how Kaeya's nightmares had persisted through his adulthood.
He had only found out, when Kaeya had fallen asleep on the counter, probably too tired after doing all his works that day and adding up the alcohol.
And as much as Diluc would love to just wake him up and kick him out of the tavern, Kaeya looked too peaceful when asleep. Far from the lies that etched in his mouth whenever he's wide awake.
Diluc's brotherly instincts kicks in, an urge to protect this Kaeya despite everything that had happened, because even though they hated each other, Diluc still cared for him like he always did.
So, he picked him up easily, bringing him to his bedspace in the tavern, and tucked him under the sheets.
Not even after a few minutes later, Kaeya had started to stir, his eyebrows furrowed accompanied by his muffled cries, and then his eyes shot open, slightly startling Diluc in the process.
Kaeya blinked, taking every information around him at once, and then froze when he saw Diluc who was removing his black coat beside the bed.
“You passed out earlier and it would seem to be my responsibility if I kicked you out and die, ” Diluc cuts him off, before he can even fully say his question.
“Oh,” he replied, sleepiness still lingering with him.
Diluc sits on the side of the bed with a book on his hand, acting as if the other wasn't beside him. “You can go sleep there, I'll just read then sleep when you're gone tomorrow.”
“Diluc,” Kaeya called, meeting his stare, “let's sleep together. Just like old times. Even just for tonight?”
A moment of silence passed, with only the sound of the crickets to be heard, then Kaeya turns to his side, his hand reaching for the book on Diluc's and placed it on the cabinet beside the bed, which gained a sigh.
“Just this once,” Diluc gives in, laying beside Kaeya who sleepily invaded his space. His shoulder relaxes with the other's touch, his eyes watching how the other's breathing had evened out eventually.
Maybe, it was never too late for him to cherish this moment too.