Katakiuchi

Katakiuchi (敵討ち Vengeance) is a unique sword, which is currently wielded by Rika with a potent Shade bound to it. It takes the form of a double edged longsword with a square-shaped cross-guard red hilt, and large golden pommel. As expected from a shade imbued item, it emits a foul chakra embodying which is key to its unique abilities. It has been stated that only those that can repress the shade's chakra are able to effectively utilize the blade without it draining their physical energy. It has to have impressive durability deflecting strikes from a chakra flow enhanced Myaku-giri, without taking damage. Nōsei has stated that the living chakra in the sword is what prevents it from being broken. This sword is claimed by Rika from one of the Yūgure sent to kill her mother. Katakiuchi has the ability to drain the physical energy of the targets that it cuts, allowing even the smallest nick to weaken opponents. This ability only drains an targets physical energy and doesn't effect their spiritual energy levels. As such it doesn't effect fully formed chakra.

While Rika is able to resist the swords effects under normal circumstances, when she is extremely low on stamina the sword could easily finish her off. As such Nōsei tends to keep a close eye on her when she is wielding it.