A kanji letter on a Demon Slayer uniform reads METSU and means to annihilate.
This is the same letter as METSU in “Kimetsu no Yaiba”.
KI = Japanese demon
METSU = annihilate
That makes KIMETSU mean “demon slayer”. The word Kimetsu doesn’t exist in japanese and it’s a coined word made by the author of Demon Slayer.
A fact behind the manga title
According to the Demon Slayer official fan book, there was another option for the manga title and it’s “Kisatsu no Yaiba”. Did you notice the difference between KIMETSU and KISATSU?
SATSU in the word Kisatsu uses this kanji and its meaning is to kill.
The author Gotoge Koyoharu told in the book that he chose “Kimetsu” because Kisatu is too straight and stimulating. But the word Kisatsu it self is used in the story as KISATSUTAI, the Demon Slayer Corps.
KI = Japanese demon
SATSU = kill
TAI = corps, troop, squad
As the author says, the kanji KILL is very direct. METSU sounds somehow classical and poetic. The letter Kill is associated with to attack someone with edged tools. On the other hand, the letter Metsu has a nuance to vanish something with special weapon including sorcery power.
If a demon is simply a villain, the kanji kill may be more suitable. But all the demons in Demon Slayer were originally humans and Tanjiro called them “sad creatures” because it’s not their own intention to kill and eat humans.
And this is just my opinion, Satsu sounds like doing it for personal grudge, but Metsu seems doint it for bigger goal.
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