After taking the data from my body, Kashiwagi-san looked at the data printed on the computer and nodded.

“Hmm, I see.”

“What is it?”

I asked as I sip my sports drink, having been stripped down to my underpants for the inspection.

“Ah, now I know what your inhuman athletic prowess is all about.”

“Eh? W-what was that!”

“I don’t know. I just found out that I don’t know.”

“… huh?”

When I looked at her and asked her which one it was, Kashiwagi-san removed her gaze from me.

It was the usual harbinger of a long story.

“There are two types of human muscle fibers: fast-twitch muscles, which are good at exerting instantaneous force, and slow-twitch muscles, which are good at exerting endurance force. Yamamoto’s muscles, however, had been altered by hypertrophy, They became an “unknown muscle” that possessed both the characteristics of fast-twitch and slow-twitch fibers.”

“You don’t know because it’s an unknown muscle…”

“That’s it. Can I give your muscle data to Tohsaka? He is a surgeon, but he studies muscles too. I think he will be surprised too.”

“To Renji-san? Yeah, it’s good! I hope this will repay him in some small way.”

As we talked, I looked at myself in the mirror right next to me.

Indeed, I have moderate muscles, but compared to my previous self, I look much weaker…

“But I understand now. That’s why I have strength even though my body looks so weak.”

Upon saying that, Kashiwagi-san also fixedly gazed at my body.

“… You think you have a weak and frail body? From my perspective, your body is… incredibly, good… I mean, no, nevermind!”

Kashiwagi-san muttered something in a small voice, then blushed and quickly tried to cover it up.