How We Met Again

Chapter 34: Insomnia

"Wrong. Try again."

It was Saturday.

"D...Diffraction!"

"Wrong. Try again."

It was Saturday, and there were two days left until the first exam. Two days left until the culmination of Yotsuba's efforts. Two days left until we would have the final verdict on whether she had succeeded -- or succumbed to the ever-present threat of failure.

"Um... reflection?"

"Wrong. One more time."

Yet even as I sat on the couch in the Nakano apartment, my gaze locked onto Yotsuba's scrunching face, my main concern wasn't her academic prowess. In fact, in that moment, it was the furthest thing from my mind.

"Geez... uh... oh, wait. The light is bending... refraction?"

"Correct. Next card."

Instead, I was entirely preoccupied with the sheer exhaustion that was written across her face.

I'd arrived at the Pentagon early Saturday morning, and we'd gotten straight to work. A spread of snacks in front of us, gaps opened up on the coffee table -- we'd fallen into our usual pattern near effortlessly. Yet, as the hours slipped us by, absorbed seamlessly into the time-eating lope of constant activity, the small ball of worry in my stomach grew only stronger and stronger.

She needs to actually sleep.

Miku was holed up in her room, presumably spending time virtually with her friend in Tokyo, while Ichika and Itsuki had both independently left the house. While I was perfectly happy to have one-on-one study time with Yotsuba, the arrangement we found ourselves in had once again left us stuck with Nino as the only other person in the room.

Luckily, thus far, she'd managed to mostly keep her comments to herself.

"Um... Uesugi-san, I don't think I totally understand what this 'critical angle' thing is -- why is there a hard cut-off for when light has total internal reflection?"

"Look, it's in the math itself..."

As I explained Snell's law to Yotsuba, I could feel Nino's eyes occasionally glancing over at us. Or, maybe at me. It made my skin prickle slightly -- but there was nothing to be done. I had more important issues to deal with; helping Yotsuba to study.

Though, perhaps an even higher priority was getting Yotsuba to rest.

As my eyes traced the contours of her face while I spoke, as they ran along the curve of her cheeks and the fullness of her lips, I could see the signs of her exhaustion, the strain of unrelenting effort. It seemed as though the intervening night since she'd announced her intention to focus on studying had done nothing to blunt the edge of her sleep deprivation.

If anything, the problem almost seemed worse.

"I think I see... so, it's the incident angle that allows a refraction angle of pi-over-two... that... that makes sense, I supp--"

"Yotsuba," I said quietly.

There was a moment of silence as I cut her off, Yotsuba just blinking at me. Then, tilting her head slightly, she looked at me inquisitively.

"Um... yes?"

"Don't take this the wrong way," I murmured, "but... let's stop. You need to rest."

"H-huh? Don't be silly, Uesugi-san -- I'm totally fine! I can handle at least this much!"

As she spoke, she dramatically flexed her bicep, grasping it with her hand. I silently raised an eyebrow, unconvinced. Yotsuba's eyes, trained on me, wavered... and then she looked back down at her textbook, slumping.