## Signal Processing

### Work Text:

Kaidou couldn't stand it anymore. Could not stand it.

Regular routine was being broken. After club practice, he and his sempai would go jogging silently. They would reach the river, and he would silently practice his swing while Inui collected data silently. Sometimes some small words of advice would arise from the calculated data, and maybe a grunt while he did his resistance exercises. Then they would walk home, silently parting ways. If Kaidou was lucky, there would be a kitten on the way that no one would see him petting in silence.

Silent being the key word.

Kaidou liked silence, which is probably his biggest problem with Momoshiro.

But today, Inui sits there scratching in his notebook louder than any other time Kaidou had been this close to data collection. The older boy grunted and scribbled and erased and sighed and scratched out what he wrote. Over and over again.

Kaidou just couldn't take it anymore. Setting down his string of towels, he steps out of the river towards where Inui sits on the bank of the river. He is so intent that he doesn't even notice Kaidou's approach.

"Ah," Kaidou says looking over his sempai's shoulder into the notebook.

"Ah," a startled gasp from Inui.

Kaidou watches the scribbling, erasing, scratching for a few moments. There were a string of numbers and symbols. He thought that he recognized his sempai working on a similar equation before. He also knew that the star-burst pattern symbol was representative of Kaidou and the two overlaid triangles were Inui. Sempai was calculating something related to them. Doubles play, Kaidou wondered, or something else?

"Sempai."

"Kaidou, do you think this is an impossible calculation?"

The bandana-clad teen falls into the grass next to his sempai. The sun slowly setting behind him as he accepts the proffered notebook. He glances at it for a moment, silently figuring out what kind of problem his sempai is working on. Kaidou flusters and feels his face warm, unnoticed by Inui.

"Sempai, is this a signal processing equation?"

"Yes."

Inui nods his head. Adjusting his glasses and glancing upwards toward the sky. He watches the river for a few moments, then toward the bridge. It doesn't take long for Kaidou to figure out that he is purposefully not looking towards his kouhai while he examines the notebook.

"You do? What-"

Inui lifts his head and meets Kaidou's eyes. Though he cannot see his sempai's eyes behind the thick glasses, Kaidou pauses for a moment and imagines what they look like.

He notices his sempai shifting uncomfortably under the gaze but refusing to break it.

"Love is an unreal number..."

"Ah. Is that so," Inui trails off after snatching the notebook back and continuing his calculation.

The brief moment is broken between them. Inui may or may not have realized that Kaidou fully understood what he was calculating, and the younger boy waits patiently at his side while it sinks in. Kaidou sits silently, already having his training disturbed and thinking he will have trouble going back to it. Inui's back stiffens and he suddenly draws a thick X across the whole page. He watches the furrowing of eyebrows on his sempai, watches him lick his lips as he sets his pen down.

"Kaidou."

"Yes?" Growing impatient.

"By my calculation..."

"Yes, sempai?" Practically growled.

"97% chance that you will hit me when I do this..."

Inui leans in, laying a hand on Kaidou's shoulder. The surprise of lips meeting lips doesn't come from the younger boy. In fact, Kaidou is returning the kiss with enthusiasm.

The surprise is actually because, after they pull away from each other and stare a moment, Kaidou whacks Inui over the back of the head.
Inui laughs at Kaidou's glare.

"3% chance you would hit me because you did not want it. 16% chance you would hit me because we are not in a private place. 78% chance you would hit me because I was attempting to calculate whether or not to kiss you and interrupted your training because of it."

"Was it worth it?"

"No."

Kaidou hisses at this. He makes a move to stand up, clearly offended at his sempai's dismissal. Inui grabs his wrist before he can get far.

"No, because this data is useless. It is an impossible calculation. There is no mathematical logic behind this action, even though I can list a gross of reasons. Please forgive me. Kaidou, I like you."

Kaidou mumbles something, and sits back down. Inui pushes him to repeat it, unsure of what he heard. The younger boy hisses and looks up and over to his sempai without moving to face him again. Inui brings his hand to Kaidou's cheek and requests once more than his kouhai repeat himself.

Kaidou lifts his hand to meet the one touching him.

"Sempai... I said... name... Kaoru." He still mumbles, but Inui understands this time.

"Kaoru... Kaoru... Kaoru," he whispers, secretly trying it out in his mouth rather than just enjoying watching his kouhai faintly blush. "Ii data."

The sun slowly sinks below the horizon as Inui leans closer once more, glasses glinting with the last of the light.