The faint sound of a guitar being strummed echoed softly through the apartment, so low that their neighbors on the other side of the wall probably didn't even hear it. Santa smiled from the kitchen. Not only could he hear it, he could pick out each individual note and if he closed his eyes he see Yuki's fingers dancing over the strings. The melody wasn't one of his favorite songs, but he hummed along anyways. It was something Yuki had picked up from another band, a song he liked just for the way it sounded and Santa had a feeling that it would be inspiration for something else. Yuki did that sometimes, took a song he'd heard and then twisted it around, rearranging the notes and adding embellishments until it sounded nothing like the original except to Yuki.
Santa stirred a spoonful of sugar into his tea, being careful to keep the spoon from clinking against the sides – not out of any concern for the cup but rather because it drowned out the sound of the guitar. The spoon went into the sink as soon as he was done, a move which would have shocked his parents if they could see it. Living with Yuki had made him a lot neater, not out of any sort of effort on either of their parts, it had just sort of happened. Yuki was like that. Santa hadn't even notice that he'd shifted some of his behaviors to better fit with Yuki's quiet lifestyle until after the shift was complete.
Still, he didn't mind changing, especially as it made him feel somewhat closer to Yuki.
His feet barely made a sound as he padded through the apartment. That was another change that had snuck up on him, how quiet he could be without even thinking about it. Not that Yuki minded when he was loud, which still happened fairly regularly, though not as much as it used to. Santa liked being quiet, most of the time, because it was almost like he appreciated the moment more when things were silent, and it had led him to appreciate all of the subtler sounds that came with Yuki. His heartbeat, for example, which slowed or quickened depending on what Santa did, or his breathing – the tiny gasps Yuki made when Santa was inside him, or the quiet moans Yuki tried to hold back while Santa was nibbling on his ear or shoulder or neck, and even the way Yuki tried so hard to keep quiet – usually failing – when Santa had him pinned to the bed, his mouth around Yuki's erection and his fingers moving inside.
The bedroom door was open and Santa leaned against the doorframe to watch, not wanting to walk in and disturb Yuki with his guitar. His lover had his head down, purple hair fanning off to the side of the guitar and he was mouthing something, words not given breath while he played through the same short refrain over and over again.
Santa sipped his tea and let his mind wander through various scenarios of drum arrangements that could go with it, or whether it would be better just to leave the guitar melody alone, maybe add in a second bass or just Sakuya's voice. The melody shifted with each refrain, morphing into something that sounded a lot more like Lucifer.
It took Santa a moment to realize the music had stopped and he looked up from his tea to smile over at Yuki. "It sounds nice." His voice came out hushed and a little reverent. He really was in awe, sometimes, at how good a musician Yuki was.
"Thanks." Yuki's smile seemed to make the room a bit brighter and he shifted his guitar, moving over towards the foot of the bed in case Santa wanted to sit down.
Taking another sip of his tea, Santa crossed the room, setting the cup on the bedside table before laying back on the bed next to Yuki. He reached out and rested his hand on the bare skin exposed by the back of Yuki's shirt.
"What's the song about?" In his head Yuki had probably already worked out the whole reason for the melody, and though he'd probably leave it up to Sakuya to mix in lyrics Santa had learned that melodies always had a reason with Yuki and even if there weren't any words it still had some meaning. Santa liked to think it was the songs without words that had the most meaning.
"I haven't decided yet," Yuki said as he shifted on the bed, turning on his side and laying back so that Santa's arm curled around him and he was facing Santa. The smile on Yuki's face said that he probably did have a meaning attached to the song, he just wasn't going to tell anyone yet.
Santa smiled back. That meant it was probably something romantic, and something he'd have to kiss – possibly more – Yuki for later. Or now.
Their lips met softly, no real fervor behind their kiss and it was as quiet as the strains in the guitar. Santa's hand still rested on the small of Yuki's back and he brought the other up to rest on Yuki's hip. Tongues darted out, just briefly, neither of them doing much to deepen the kiss but the possibility was always there, it just needed one of them to ignite the spark that was simmering low between them.
Yuki pulled away slightly, leaning back enough of that he could look Santa in the face. One of his hands reached up, brushing a stray lock of Santa's hair away from his face.
"I think I'll keep the song to myself, just for a little while longer." Yuki whispered with a smile and then started humming.
Santa was pretty sure he could guess what the song was about, and the way Yuki's hands dipped underneath the hem of his shirt dispelled any doubts.