|User||Ichigen Miwa (former)|
|Anime Debut||K: Missing Kings|
|Manga Debut||K -Count Down-|
A katana with a black hilt, and a peculiar shaping near its hilt that juts out. The sheathe is dark purple, tied with a much lighter purple cloth. when it is drawn, it appears to have enough space in its side, so it often draws out in a tilted motion, rather than straight out. Its sheath features the Colourless Clan's insignia.
When Yukari channels his Aura into Ayamachi, it glows a bright violet.
Ayamachi was given to Yukari after a challenge with Ichigen. After Yukari manages to land a hit on Ichigen, he acknowledges that Yukari has the skill to land a significant blow on a King such as himself, and that he always intended on giving this sword to Yukari. Ichigen believes that Yukari is the person that should wield Ayamachi. Its name isn't just a name, and its meaning is up to Yukari's own interpretation. Yukari claims that Ayamachi contains all of his passion and ambitions, making it strong and full.
Ayamachi's name means "fault", "error".