The United Nations Party is a political party in killer7. In spite of its name, it has nothing to do with the real-world United Nations, a summit of most of the world's sovereign states; rather, the term refers to its designs to "unite" all of the world's "nations" under Japanese rule. As such, it is a direct throwback to early 20th Century Japanese imperialism and a highly aggressive example of extreme nationalism. Given this, it is most likely very conservative in its governmental policies, although its position as a reactionary counterrevolutionary party could actually lead to it being considered radical. It has local chapters in many countries throughout the world, in order to better facilitate its ultimate goal.
UN Party doctrine is known as the Yakumo, meaning "eight clouds," an allusion to an ancient Japanese poem, and possibly the writer Lafcadio Hearn, a westerner who took the name Koizumi Yakumo when he naturalized into a Japanese Imperial subject. The document was drafted by Tohru Fukushima, who was later forced to flee Japan in the face of physical attacks by his political opponents, only to be ultimately assassinated by the killer7. The Party tactically gave pieces of the Yakumo to various strong leaders worldwide, notably Andrei Ulmeyda, in the hopes of extending their range of influence in more subtle ways on top of their mainstream methodologies; in exchange, the bearers gained authority, political cachet, and certain mystical powers.
Its most prominent member is Kenjiro Matsuoka, also known by his nickname "Matsuken." As a young man, Matsuken ascended the ranks of the UN Party and eventually became one of its most influential members. However, after the launch of nuclear warheads at Japan and Matsuken's subsequent failure to save the country following the breakdown of talks at the KAKU building, party ancients Shinya Akiba and Hiroyasu Kurahashi order him to commit suicide in atonement (a further example of the UN Party's conservative stance, as this mirrors the ancient Japanese ritual suicide practice of seppuku.) However, he turns their gun and shoots both, destroying their heads but failing to kill them, following which they merely continue to mock him. The desperate Matsuken is saved thanks to the intervention of Kun Lan, who touches him with his God Hand, awakening a certain power in him, and then spirits him away. From here, Matsuken takes control of the UN Party and leads it to power. As leader of the party in power, Matsuken becomes the Prime Minister of Japan.
Under the UN Party, Japan begins a series of cultural and military attacks on the rest of the world, particularly the United States. If, during the events of Lion, the player elects to let Matsuken live, the UN Party will succeed at world domination; otherwise, it will be destroyed, as will Japan itself.
The fact that Matsuken dispatched Oota and Kuramoto, members of the opposition Liberal Party, to rendezvous with the United States's governmental representatives suggests that the UN Party may have under-the-table dealings with its political enemies.