While analyzing the relic in the basement lab, Tatsuya's intercom buzzed. With only him and Miyuki in the house, he answered without hesitation.
"What's up?"
"Onii-sama, dinner's ready. Sorry it's late," Miyuki's voice chimed.
"Right."
Realizing he hadn't eaten, Tatsuya paused his work and headed to the living room. Miyuki greeted him with a mischievous smile.
"That apron," Tatsuya noted.
"Notice anything?" she teased.
"The one you bought with Mizuki?"
Miyuki wore a brand-new apron, sparking Tatsuya's memory of her outing with Mizuki.
"As expected of Onii-sama. You always notice," Miyuki said, beaming.
"It suits you. Makes me not want anyone else to see," Tatsuya said plainly.
"Onii-sama!" Miyuki blushed.
Tatsuya's lack of embarrassment let him say such things casually, but for Miyuki, who harbored feelings she knew she shouldn't, his words sent her heart racing, her face flushed crimson.
"Let's eat. It's ready," she said, composing herself.
"Right."
More a late-night snack than dinner, they ate without concern, knowing neither would sleep soon. Miyuki barely touched her food, entranced by Tatsuya enjoying her cooking. She could go without eating, so Tatsuya didn't comment.
"I'm heading back to the lab. What about you, Miyuki?" he asked.
"I've got assignments to finish before bed," she replied.
"Keep at it," he said, gently patting her hair before returning to the basement.
Miyuki watched him go, then erupted in joy, bouncing with excitement. "Onii-sama praised me! He told me to keep going!"
Alone, she shed her usual composure, letting her emotions run free. No one else would see her like this. After a brief outburst, she steadied herself.
"Time to clean up and tackle those assignments. Onii-sama cheered me on, so I have to try hard."
Her rule was to keep such moments short, lest she lose herself to joy over Tatsuya's praise.
Hours later, past midnight, Miyuki sighed at her desk. One assignment stumped her completely.
"I envy Onii-sama's brilliance," she muttered.
Once wary of him in middle school, a certain incident had made her utterly devoted to Tatsuya. Their classmates were shocked by their transformed bond after summer break.
"I could ask Onii-sama… but he's busy with the relic. I don't want to disturb him."
Miyuki knew why Sayuri visited—to drag Tatsuya, a prodigious researcher, back to headquarters. He didn't need to attend high school, but he enrolled at First High because Miyuki did. As a Yotsuba Guardian, he couldn't leave her side.
"Thanks to Onii-sama's tutoring, I got top grades," she mused.
Her grades were always excellent, but she attributed them to Tatsuya's help.
"I'm the only one who gets Onii-sama's attention… but if I let him go too free, I might get left behind."
She didn't want to be a burdensome sister, yet craved just enough of his care to feel needed.
"There are so many rivals around Onii-sama now…"
Miyuki shook her head, panicking. "Rivals? I can't be his lover…"
She'd never resented their blood tie, but it barred her from being with him romantically. Her place at his side, though closest now, would eventually be taken.
"Honoka and Shizuku get to act spoiled with him. Nanatsu-senpai and Ichihara-senpai are close to him too…"
She knew many girls were drawn to Tatsuya. She believed only Mizuki was a pure friend.
"Erika and Eimi seem aware of him too… Even Ono-sensei and Yasuku-sensei seem overly touchy with him."
Sayaka, Koharu, Airi from Third High, and Kanon—she knew they all had feelings for Tatsuya. More sensitive to his admirers than he was, Miyuki's frustration grew daily.
"Why am I just his sister?"
Realizing she'd spoken aloud, she shook her head furiously. It was a futile thought, meaningless to voice.
"What am I thinking? Being Onii-sama's sister is my exclusive privilege!"
No one could take that role, not even Shizuku, who acted sisterly but could never be one.
"Focus on the assignments…"
Unable to solve the problem and reluctant to disturb Tatsuya, she decided after thirty minutes to ask him tomorrow.
"That's it. I'll sleep now. Onii-sama has an early morning."
Tatsuya trained at Yakumo's temple daily, despite late nights, without fail.
"He won't overdo it… Onii-sama will be fine."
Her confidence came from knowing his true magic—a superior magician, her savior. That trust anchored her.
"Good night, Onii-sama," she said, glancing toward the basement before slowly undressing and slipping into bed.
--+--
T/N: Although I'm an inexperienced Editor, I do have a Patreon account! Although it seems like I don't have many supporters right now, my webnovel will be released in full every day, and the advanced chapters will be uploaded to Patreon.
It may not be worth it now, but who knows, it might be different in the future. Who knows!
patreon.com/DaoistRoeoNQ
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