Wisteria

Wisteria is a plant used widely by the Demon Slayer Corps in their war on demons. Its real-world counterpart is also poisonous, its seeds containing a toxic compound that can sicken humans who ingest it.

The plant carries a special place in Corps history. After the Demon Slayers once rescued a family from demons, that family built a wisteria flower into its crest so members could recognize the home and stay there without charge. The flower's repelling power shapes everyday Corps practice, from incense burned in dangerous areas to the barriers that hold demons in place.

Wisteria serves many roles. Grown around a home or burned as incense, it keeps demons away, as Gyomei Himejima did at his temple. During Final Selection it seals demons inside Mount Fujikasane, whose name refers to being covered in wisteria, so the captives can serve as a test for recruits.

Its poisons can paralyze ordinary demons and immobilize the Lower Ranks of the Twelve Kizuki, hampering regeneration, movement, perception, and Blood Demon Arts. In strong enough doses, as Shinobu uses, the poison can dissolve almost any demon. Shinobu shaped her blade to inject the toxin and even rebuilt her own body so every cell carried poison, turning herself into a roughly thirty-seven kilogram dose meant to destroy Doma from within. Wisteria also yields antidotes, is refined by Shinobu into a medicine that turns demons back into humans, and is used to engrave a member's rank onto the back of their hand after Final Selection.

The Demon Slayer Corps uses wisteria broadly, with Shinobu Kocho its foremost practitioner through poisons, antidotes, and her self-modified physiology. Gyomei Himejima burned it as incense for protection, while Hinatsuru carried wisteria-laced kunai that struck Gyutaro and were later used by Tanjiro Kamado. The plant debuts in Chapter 6 of the manga and Episode 4 of the anime.