Tengen Uzui (宇う髄ずい 天てん元げん Uzui Tengen) is a major supporting character of Demon Slayer: Kimetsu no Yaiba and a major character in the Entertainment District Arc. He is a Demon Slayer of the Demon Slayer Corps, and the Sound Hashira (音おと柱ばしら Oto Bashira).

Tengen is a very tall, wide-set man of a bulky, muscular build with lightly-tanned skin. His hair is white and of uneven length, the longest strands reaching his shoulders, and is styled with three more notable, shorter clumps arching up to fall as bangs between his eyes and on either side of his face. He has quite thin, maroon eyes that appear to slant inwards, each with one long eyelash flowing to the far side of his face.

During his days serving Demon Slayer Corps, Tengen wears a sleeveless and dark turquoise version of the standard Demon Slayer uniform, along with a wrap of burgundy cloth around his calves where his hakama pants tuck in, and white-strapped sandals. He also wears two thick, golden rings around his upper arms and what appear to be a pair of fingerless blue gloves, secured around his middle finger with a band of white and his wrists with another set of thinner gold rings, this time with two on each side. As well as this, Tengen sports a white head-wrap that covers his hair, leaving only a thin ponytail visible to fall behind his head from between its layers, which is adorned with a large headband of pale gray that’s decorated by six light pink gemstones, three large and arranged in a line, and three small and arranged in a triangle to the far left. A chain of smaller, pale blue gemstones hangs from each side of this headdress, framing his face, and he also wears what looks to be red eye make-up around his left eye, consisting of alternating large and small dots that run inwards, towards his eye.