"Demon Slayer: Kimetsu no Yaiba – To the Hashira Training," which featured the intense "Akaza's Assault" sequence, has been absolutely crushing the box office since its Japanese premiere. After August, it continued its phenomenal run across Asia, sparking a massive pilgrimage to theaters in places like Taiwan and South Korea.
But with the film's release, even though the manga has concluded, fans are still dissecting every plot detail. Recently, a specific line from Akaza – "every cell in my body" – ignited a fiery debate on X (formerly Twitter), with many questioning its historical accuracy, especially given Akaza's Edo period origins.
▼ It even unexpectedly became a trending topic on X.
The whole discussion kicked off with a post arguing that Akaza couldn't possibly have known about "cells" on his own. The concept of cells was first proposed by British scholar Robert Hooke in 1665, and Western biology wasn't formally introduced to Japan until the Meiji era. Therefore, the idea of "Akaza understanding cells" was deemed illogical, unless, as one netizen quipped, "he secretly attended Imperial University."
(In this scene, Akaza notices something subtly different about Tanjiro, and his inner monologue is: "Every cell in my body, from skin to hair, tells me I must kill this guy right now.")
This post, predictably, sent fans into a hilarious brainstorming frenzy. Many speculated that Muzan probably just dumped a pile of research on his subordinates, demanding, "Read this by morning, report by noon!" or even ran a private cram school for his Upper Rank demons. "He doesn't just hold abusive boss meetings; he holds academically abusive classes too!" one fan joked, picturing Muzan as a tyrannical, sweatshop-style professor.
Others took the speculation even further, suggesting that besides searching for Blue Spider Lilies, Muzan might have been secretly brushing up on his medical knowledge, infiltrating various institutions to keep up with scientific advancements, and then relaying that info to his Upper and Lower Rank demons.
Meanwhile, some research-oriented netizens offered a serious counterpoint: Japan actually started producing its own microscopes, like the Nikon JOICO series, during the Taisho era. So, the concept of "cells" wasn't entirely out of the realm of possibility, suggesting it might not be a plot hole after all.
(Note: "Demon Slayer" is set in the Taisho era.)
Another netizen pointed out that while the concept of "genes" appeared in 1865, it didn't truly become widespread until the Showa era, implying that some of the terminology might have been slightly embellished in translation.
While most of these discussions are pure fan speculation—after all, the series isn't meant to be a historical documentary—they certainly highlight the incredible attention Japanese fans pay to "Demon Slayer." They're even diving deep into medical history for it! You've gotta hand it to them for their dedication, lol.
via： togetter