Reina wasn't expecting any visitors that evening. She had just finished organizing some old sketches and was debating whether to grab a late snack or just let ANIER nag her into drinking more water before bed. Then— knock knock knock.
"…?"
She tilted her head. Not Himari. Not Sei. Definitely not the principal—she always barged in without knocking.
Reina walked to the door and slid it open.
Standing there was Shion Kurobane, clutching his bag and looking… awkward.
"Saeki-san," he said, bowing slightly. "Sorry to disturb you so late. May I come in?"
Reina blinked, a little surprised. "…Kurobane-kun?" She stepped aside. "Sure. Come in."
Shion entered carefully, like he was afraid of stepping on sacred ground. His eyes darted around the room—stacks of notes, shelves of tools, monitors softly glowing. And of course, the ever-hovering halo above Reina's head.
"So," Reina said, folding her arms, "what do you need? It must be important if you came all the way here."
Shion scratched his cheek, clearly embarrassed. "Ah… yes. Actually, I was hoping you might have… a microphone I could borrow."
Reina raised an eyebrow. "…A microphone?"
He nodded quickly. "Yes. I, uh, broke one of our club's best mics during a recording session. I was too careless, and… well, replacing it will take time. I thought maybe—since you're always inventing things—you might have something."
Reina tapped her chin. "A microphone, huh… Well… I do have one. But it's not exactly… normal."
"Eh?"
Without explaining further, Reina walked over to one of her storage cabinets and began digging around. Boxes clattered. A faint "ow" escaped her lips when something fell on her foot. Finally, she pulled out a sleek, cylindrical device—silver, with a faint blue glow pulsing at its center.
She held it up. "Here. Experimental prototype."
Shion's eyes widened. "…That looks way too advanced to be just a mic."
"It's a microphone," Reina insisted flatly. "But, with some… upgrades."
ANIER's voice suddenly chimed in, echoing faintly through Reina's lenses.「Correction. Experimental audio-input device utilizing noise-canceling fields and ultra-high-resolution capture. Output fidelity: approximately 4.8 times higher than current industry standards.」
Reina groaned. "ANIER, you didn't need to flex like that."
Shion blinked. "…Did someone just talk?"
"Oh, right." Reina reached into her desk and pulled out another small device—shaped like a thin badge with a glowing icon at the center. She handed it to Shion. "Here. Put this in your pocket. It'll sync with ANIER."
Shion looked confused but obediently clipped it on. A second later—
「Connection established. Good evening, Kurobane Shion. I am ANIER, Reina's AI partner. I will now explain how to use the microphone.」
Shion nearly dropped the badge. "Wha—?! There's a voice inside this thing?!"
Reina smirked slightly. "That's ANIER. Don't worry. She's… mostly harmless."
「Mostly? I have never harmed anyone. Data shows Reina enjoys teasing me unnecessarily.」
Reina ignored the AI and handed the microphone over. "Anyway, it's accessed through ANIER's server. That way, it can capture sound with extreme accuracy, even subtle vibrations. Basically, no matter where you are, the audio will sound beautiful."
Shion carefully cradled the microphone like it was made of glass. "…This… this is incredible. If this really works, it could elevate our entire performance recordings…"
Reina shrugged. "It'll work. Just don't drop it."
「Or spill juice on it. Or attempt to dismantle it. Or use it as a drumstick.」
"W-why would I do that?!" Shion protested.
Reina allowed herself a small chuckle. "Relax. Just treat it like a normal mic. ANIER will handle the rest."
Shion gave a deep bow. "Thank you, Saeki-san. Truly. I… I'll take good care of it."
"…Alright," Reina said, brushing a strand of hair behind her ear. "But remember—it's only a loan. I still need it for some tests later."
"Of course! I'll return it as soon as possible."
As he moved toward the door, ANIER suddenly added:「Recommendation: you should let him test the microphone here. It would ensure optimal calibration for his voice frequencies.」
Reina sighed. "…ANIER, do you just want to hear him play?"
「Affirmative.」
Shion looked between them, flustered. "U-um… I could… sing a little, if that's okay?"
Reina crossed her arms, pretending to look uninterested. "…Do what you want." But her halo hummed faintly, betraying her curiosity.
Shion set the mic, adjusted his posture, and softly began to sing. His voice—gentle, resonant, and pure—filled the lab. The mic captured every nuance, crystal-clear, as if his voice was woven directly into the air.
Reina froze.
ANIER reported in her HUD:「Emotional response detected: calmness +12%, admiration +8%, accelerated heartbeat +6 bpm. Should I log this as "Reina enjoying the performance"?」
"…Shut up, ANIER," Reina muttered, cheeks faintly warm.
When Shion finished, he lowered the mic, visibly nervous. "…Was that okay?"
Reina adjusted her glasses, forcing a calm tone. "…Acceptable. The mic works."
But ANIER betrayed her again.「Correction: test subject's singing produced emotional satisfaction rated at 92% in Reina. She really liked it.」
"ANIER!"
Shion laughed awkwardly, scratching the back of his neck. "…I'm glad it worked then."
He bowed again, thanked Reina profusely, and promised to return the mic soon before leaving the lab.
When the door closed, Reina slumped into her chair, covering her face. "…This is going to be annoying."
「Correction: delightful.」
Reina groaned.