The Yakumo' (八雲, eight clouds) is a document in killer7 that outlines the foreign policy of the United Nations Party, whose stated purpose is to unite all the countries of the world under Japanese rule. It was originally drafted by the Union 7 in 1953. Additionally, it contains magical properties allowing the bearer of any of its pieces to create Heaven Smiles or to transmute normal humans into Heaven Smiles. This might suggest that it was infused with some of the power of Kun Lan's God Hand.
In Sunset, the Liberal Party dispatches Japanese assassin Julia Kisugi to retrieve the Yakumo from Toru Fukushima, the leader of the United Nations Party in Japan. Following the fighting at the party ancient's restaurant, Kisugi murders Fukushima but is left empty handed as Jean DePaul, another assassin in the employ of the International Ethics Committee, had already obtained and smuggled out the Yakumo. Following DePaul's own death at the hands of the killer7, its whereabouts is unknown, though according to DePaul, now a Remnant Psyche, Kenjiro Matsuoka, the leader of the UN Party following Fukushima's death, had got his hands on it.
Some time later, Andrei Ulmeyda is found to have obtained a piece of the yakumo, and is using its powers to conduct medical experiments on himself for the betterment of his cultists, using his pharmaceutical organization First Life as a front for his activities to avoid unwanted attention. This ends after the confrontation between Ulmeyda and the killer7, after which the yakumo may or may not have been destroyed, though Clemence carries on Ulmeyda's legacy and so may have inherited his powers.