Obanai Iguro is a major supporting character of Demon Slayer: Kimetsu no Yaiba. He is a Demon Slayer of the Demon Slayer Corps and the current Serpent Hashira.
As a Hashira of the Demon Slayer Corps, Obanai was one of the most powerful and skilled swordsmen in the entire organization. This was shown during the Hashira Training Arc where he was entrusted to teach all the other Demon Slayers about sword wielding techniques. Obanai makes use of a unique swordsmanship style that utilizes slithering motions to bending his sword and attacks in impossible ways, allowing him to weave through narrow openings with ease despite wielding a standard wooden sword. His swordsmanship prowess allowed him to keep up with the Demon King himself, Muzan Kibutsuji.
Serpent Breathing: A Breathing Style Obanai created himself and mastered. This swordsmanship style makes use of twists and turns similar to how a serpent slithers to attack in strange ways. Obanai also learnt to incorporate his pet snake, Kaburamaru, into this Breathing Style, making it extremely effective in combat as seen in the final battle where he could keep up with a weakened Muzan while completely blind and still managed to drive him into a corner.
Twisted Nichirin Katana: Obanai carries around a heavily modified Nichirin katana similar in appearance to an Indonesian Kris Sword, with the sword's shape modeled into waves resembling a twisting snake, which is lavender in color. His katana's hilt has a gold circular shape engraved with two snakes connected by several plant-like patterns. The words Destroyer of Demons is engraved on the side. Obanai also carries along a special scabbard made of leather held together by a weak magnetic pull that opens up whenever he uses his katana. It is designed so that Obanai unsheathes his sword vertically instead of horizontally.