The second day of quarantine dawned, and Minamoto Senya was in unusually high spirits. For the first time, Tōma Kazusa finally acknowledged that his fundamentals were solid.
The simple beginner pieces he'd been stumbling through could now be set aside, and he had moved into the next stage of learning.
But with the sudden leap in difficulty, resistance naturally followed.
Listening to Kazusa play Clair de Lune was like hearing the moonlight itself turned into music. As its title promised, the notes shimmered like pale silver waves across a darkened lake, carried by a gentle breeze. A faint fragrance seemed to ripple outward, filling the night with quiet elegance. Romance steeped every measure, delicate and poetic, like a lover's voice whispering softly by one's ear.
Then it was Senya's turn.
And the picture shattered.
What emerged sounded more like a sturdy farm boy, healthy but clumsy, attempting to imitate the graceful steps of a legendary dancer. His raw stamina carried him through, and at a glance his movements weren't completely wrong—but the soul, the rhythm, the elusive essence were missing. It was a hollow shadow of beauty, all form with no spirit.
Kazusa, however, surprised him.
"Not bad," she said, cool as always. "Forget the complicated emotions, the surging high notes, the delicate arpeggios in between. At the very least, you made it through without hitting the wrong notes."
Senya sat in silence, eyes fixed on the score, replaying each passage in his head. To Kazusa, it looked like he had collapsed under the weight of comparison between his own crude attempt and her polished performance.
Despite her aloof exterior, Kazusa was a kind girl. Especially toward the people who mattered to her. Underneath her cool mask, her heart was soft, like the custard inside the cream puffs she adored.
Encouragement didn't come easily to her—it wasn't in her nature to stir people's emotions with words. But now, seeing Senya withdrawn, worry bubbled up inside her. And in her flustered urgency, the words tumbled out more gently than she'd intended:
"This piece looks simple on paper, but to really capture its beauty takes time. You have to bring out dynamics, create layers in the sound, make the left and right hands dance at different speeds. It has more traps than you think. When I learned it, it took me… half a month before my mom was satisfied."
That last part was a lie.
The truth was, Kazusa had mastered it in under three days. She had inherited Tōma Yōko's monstrous musical talent, and in her early years of piano, no piece had ever blocked her path for half a month.
But she said it anyway, hoping to ease Senya's frustration, to remind him that even great players struggled, that he didn't need to rush.
What she didn't know was that Senya wasn't frustrated at all. Quite the opposite—her brilliance thrilled him. The better she was, the more motivated he became.
His silence wasn't despair. He was simply memorizing the sheet music by heart.
Still, her words deserved thanks.
That day, aside from meals, Senya barely left the piano bench.
At first Kazusa sat by his side casually, arms folded, prepared to correct him as needed. But before long, her indifference melted into disbelief.
His progress was… absurd.
It was like watching a toddler, barely able to stand, suddenly skip the walking phase entirely and break into a run—no, not just run, but leap and bound with growing confidence.
Kazusa forgot her carefully planned schedule. She forgot to stop him, forgot to tell him to rest his fingers. Instead, curiosity seized her: just how far can he push himself in one night?
And so, she let him go.
From eight in the evening, through dinner, past midnight, Senya played. He played until two in the morning, stopping only to turn pages, his concentration unbroken.
Kazusa, who merely sat and listened, found her own body growing stiff and numb. But Senya looked possessed, as though enchanted by the keys themselves.
His fingers grew more agile, more obedient to his will. Each note responded to his command with increasing sharpness and clarity. Power, speed, control—layer by layer, everything was improving.
By the time he realized it, his piano skill had already risen to another level.
"…Enough. That's enough for today."
Kazusa's voice finally broke through as one piece ended, her tone firm.
Senya blinked, surfacing from his trance. Only then did he notice the clock—it was already two-thirty in the morning.
"You…"
How could he progress so fast?
From a professional's perspective, his performance still had rough edges. But this was no longer a beginner's fumbling. In less than a day, he had grasped the core of an intermediate piece and steadily polished it.
At this rate, she realized, he would completely master it in another two days. Maybe even one.
That was faster than she herself had taken.
And back then, her foundation had been much firmer than his.
Kazusa had always known he was gifted. But now, she had to admit—he might be far beyond what she had imagined.
"Enough for today," she said more softly, drawing in a deep breath. "You said it yourself: balance matters. Rest is part of practice."
She was proud of him. Genuinely.
When they finally left the practice room, Senya apologized over and over, embarrassed. He had been so absorbed he hadn't noticed the time, hadn't realized he'd monopolized the piano all day.
Kazusa didn't mind.
On the contrary, she was already rethinking the plan she had made for him. Clearly, the old schedule wouldn't hold him back for long.
After washing up, they said good night and parted ways.
Back in his room, Senya found missed calls and unread messages.
Kasumigaoka Utaha had sent the most. At first, just screenshots of her word count for the day, flaunting her productivity. Later, questions about what he was doing. The last message, sent at one in the morning, was a good-night—accompanied by a photo.
A pale arm stretched across frosted glass, slender fingers tracing the words good night into the condensation.
She had taken it in the bathroom, clearly.
An innocent gesture, at first glance. Just a clever new way to say good night.
But of course, Senya's mind leapt to the obvious: what her body must have looked like just beyond the camera's reach.
As expected of a literature girl, he thought wryly. Always so full of tricks.
Eriri had sent messages too, brimming with excited emojis. She was overjoyed—because Yukinoshita Yukino would be staying in Japan for the foreseeable future. Her school in England had switched to online classes, meaning Yukino wouldn't have to leave anytime soon.
Other friends had sent brief words of concern as well.
Senya leaned back against the headboard, typed out quick replies to each, and finally turned off the light.
But across the wall, Kazusa lay wide awake. The image of his rapid progress refused to leave her mind.
Finally, she picked up her phone and called her mother.
"Mom," she said, her voice low, "I think I saw something unbelievable today."
"You mean Senya?" Yōko's voice was smooth, amused.
Kazusa explained. A beginner who had struggled through the simplest songs yesterday had, in less than a day, reached the essence of Clair de Lune. He had practiced for over ten hours, relentless.
"…Oh~" Yōko chuckled, intrigued.
"Mom, how long did it take you to master Clair de Lune?"
"So long ago, who could remember? But listen, Kazusa—you don't need to be so shocked. When a person finds something they truly love, sometimes they reveal frightening levels of effort and intuition."
Something they truly love…
Kazusa knew what her mother was implying: Senya must have fallen in love with the piece itself.
That was plausible. She herself loved Clair de Lune—otherwise she wouldn't have chosen it for him.
But another possibility crept into her thoughts. Something she didn't dare voice aloud.
What if… his rapid growth wasn't just because of the music?
What if it had something to do with the fact that she had been sitting beside him all day?
The thought sent heat rushing through her face. She buried herself under the covers, hiding the redness in her cheeks from no one but herself.
"Try him on other pieces," Yōko said. "If he keeps adapting that fast, then it's real talent."
"…Okay."
"Oh, and good news. I'll be coming home soon."
Kazusa's reply was flat. "…Oh."
"Eh? That's all? Aren't you happy? Want me to bring you a gift?"
"No."
A few weeks ago, on Christmas Eve, the thought of her mother returning would have delighted her. She would have been counting down the days to spend New Year together.
But now? It didn't feel so important anymore.
Because there was already someone else here, someone she could talk to.
"You might not even be able to come home right away," Kazusa added. "This place is under quarantine."
"Don't worry. If I follow protocol, there won't be a problem."
"…Don't," Kazusa said after a pause. "You've been working so hard. Take a vacation instead. You wouldn't like the food here anyway—it's just cheap vegetables and pork. Not to your taste."
Silence on the other end.
Yōko understood. Her daughter's concern was touching—but beneath it lay a more selfish truth. Kazusa wanted to keep this little world of two to herself, uninterrupted.
Already? Yōko thought with a pang of jealousy. My little girl's loyalty has shifted so quickly…
"…Kazusa, you said Senya practiced for ten hours. So you didn't play at all today?"
"Mm."
"Then what did you do?"
"Watched him."
"…The whole time?"
"I brought him water. Corrected his fingering once. That's all."
Yōko pressed a hand to her forehead. "Kazusa, you don't have to sit by him constantly. You can do other things too."
She braced herself, half-expecting her daughter to blurt out But I like being by his side.
But Kazusa only murmured, "I know."
After hanging up, Kazusa lay in the dark, staring at the ceiling. Her mother's last words echoed in her mind. Maybe… she was right.
The third day of quarantine arrived.
Health inspectors came by in the morning, checked their temperatures, and quickly left.
Senya, still embarrassed about hogging the piano yesterday, insisted Kazusa take the bench first.
But instead of sitting, she went to the instrument cabinet and pulled out a violin.
"Don't worry about me," she said calmly. "You play your piano. I'll practice violin. We won't disturb each other—I'll just follow your melody."
The moment she tucked the violin under her chin, everything about her changed.
Her presence sharpened, elegant and commanding.
Senya's breath caught. She was dazzling.
Like a child proudly showing off her favorite toy, Kazusa raised her bow. Her long lashes cast shadows across her cheeks, but her eyes glittered with anticipation.
The piano, with its wide range and volume, was called the King of Instruments.
The violin, with its expressive tone and versatility, was hailed as the Queen.
Together, they formed a perfect pair.
And so, the music began.