The Western Kamaitachi Siblings serve under Shinno, the Osa of the Western Yokai. Unlike Raishin and Kagari, they are mercilless and sadistic killers, and what's more they have no sibling love for each other, and have even threatened each other's lives. They are considerably more experianced as they were able to produce more blades and sickels from their bodies and from various places, using them with lethal skills and deadly precision. They fought against Raishin and Kagari, as well as Tora to even the odds, and the battle ended with the Maduchi capturing Tora, Raishin, and Kagari.
Later in Shinno's mansion, Tora, Raishin, and Kagari were forced to duel the Western Kamaitachi once more, Nao, You, and Kyou. Despite a bloody battle, they all fell to Raishin and Kagari's sickles.
Nao is the sister of the Western Kamaitachi and self-proclaimed strongest. She's the cutter of their trio, and is very narcisstic, claiming she only appears human to be beautiful. She was killed by Kagari by feigning her broken sickles and using strands of her hair to whip the broken pieces right through Nao before slicing her in three.
The youngest sibling, You is the pusher, of the trio, meaning he knocks the humans down and Nao cuts them with Kyou applying medicine. He likes to collect the names of those he kills, and cutting off human limbs. He could not follow Raishin, Tora, and Kagari's tactics and fell to Kagari's blade.
Kyou is the other brother, and the member of the trio who applies medicine. Despite this, Kyou is a sick womanizer, having desired Kagari for his own twisted desires, he likes to smoke, and he beholds his own technique, Kenjin (Whirling Blades). He was killed by Raishin.