Zenitsu Agatsuma (我あが妻つま 善ぜん逸いつ Agatsuma Zen'itsu?) is one of the main protagonists of Demon Slayer: Kimetsu no Yaiba and a traveling companion of Tanjiro Kamado. He is also a Demon Slayer in the Demon Slayer Corps.
Zenitsu is a young man with fair skin and downward-sloped, scared-looking eyes that fade from soft brown to gold. He has short, yellow hair of varying lengths, cutting off squarely at the ends where it fades to a darker orange color, that falls in front of his face in uneven bangs. Before he became a Demon Slayer, Zenitsu's hair was originally black, but it turned the color it is currently when he was struck by lightning during his training.
For some time following the battle at Natagumo Mountain, his limbs temporarily shrunk due to Demonic poison but were able to return to normal afterward thanks to the medicine given to him by Shinobu Kocho.
He wears a paler brown version of the standard Demon Slayer uniform, which consists of a dark brown gakuran jacket, a white belt around his waist and hakama pants that extend, as well as his signature white-triangle patterned, yellow and orange gradient haori. As well as this, Zenitsu also sports a pair of tabi socks, tied at the front in 3 white bows, with the same pattern as his haori, and white-laced footwear.
Toyo (豊とよ Toyo?) is an udon street vendor.
Toyo is a man of average height and build, with a bald head and closed eyes.
Toyo wears a dull-yellow-and-black striped kimono, light pants, and dark shoes. His first appearance shows him smoking a kiseru.
Toyo is very passionate about his udon, being visibly agitated about Tanjiro Kamado discarding his bowl without eating any. However, once Tanjiro returns and orders two bowls that he finishes quickly, Toyo is pleased and thanks him for his business.
Toyo was born and raised in Asakusa. At some point in his life, he opened an udon shop in Asakusa, as he loves the city and wants to stay there.