The levels in the demon slaying team are divided according to Thien Stem – the numbering system of our Asian co-cultures.
Furthermore, in chapter 129, the blacksmith Haganezuka Hotaru revealed that the demon slayer team began classifying soldiers after Mr. Yoriichi’s sword was forged.
That is, the class in the demon slayer team as of now in the series, has only existed since the Warring States period.
According to the Q&A section in the supplementary chapter of volume 11, the conditions to become a Pillar are as follows:
1. Kill one of the Twelve Demon Moons, or…
2. Kill all 50 demons
3. If there is a vacancy in the Pillar class, a person from the Giap class can be considered to take the place
4. Everything is tied to the condition that the swordsman must be strong enough to stand in the Pillar level.
How interesting, right after the tough battle between the main character Tanjirou and Ha Ngu Rui, the Water Pillar appeared and ended the scene in just a blink of an eye.
At the time of the battle with Ha Huyen Rui, Tanjirou was in the Noble class – the lowest class in the army.
The swordsman Murata joined the Legion around the same time as the Water Pillar.
Please don’t forget that the demon slayers’ battles are watched and reported by messenger crows.
Although the hierarchy in the demon slayer team is a small detail, it is quite important, reflecting quite accurately the true strength of the swordsmen.
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