Kanji and meanings
I’ll explain the meaning of Rengoku Kyojuro’s family name. It’s very powerful name which is eligible for the Flame Hashira! 🔥
REN

REN means to smelt metal or to train oneself.
The left part of this kanji stands for fire. The right part picture a bag in which selected metals are stocked. The whole part pictures to melt metals with fire and remove impurities from them.
GOKU

GOKU means hell.
The word RENGOKU is catholic purgatory, a place between heaven and hell. The soul of the dead is purified with fire there. That’s why the kanji character with fire meaning part (REN) is used for this word when it’s translated into Japanese.
Given these background, we can say Rengoku Kyojuro’s flame is purification fire.
If you want to know the meaning of KYOJURO too, check the link below!
Kyojuro’s name meaning in Japanese

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