Hotaru Haganezuka

Hotaru Haganezuka is a swordsmith affiliated with the Demon Killing Corps. Haganezuka first appears in the manga when he delivers Tanjirou's katana to him at Urokodaki's home. He appears wearing a sunflower patterned robe and a large woven hat with floral wind chimes hanging from it. His head is wrapped in a spotted cloth and his face is concealed by a Hyottoko mask (wooden festival mask) similar to Urokodaki.

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During the Swordsmith Village Arc, Haganezuka appears with the same clothing but is seen with a more muscular build compared to his initial appearance. When the village comes under attack by Gyokko, Haganezuka is attacked and his mask is destroyed revealing his face, prominent eyebrows, and long dark hair.

(Source: Kimetsu no Yaiba Wiki)