Nin’janjin was the ruler of the Mansion of Viri at the time the Incû-Holoinas fell from the void. The fall of the Ark caused a natural disaster and sent up ash-clouds that darkened the skies, resulting in a famine. Nin’janjin appealed to his kinsman Cû’jara-Cinmoi, the King of Siöl, for help. But instead, Cû’jara-Cinmoi invaded and claimed Viri.
The Inchoroi, emerging from the Ark, sent a secret emissary to Nin’janjin. At this point, they had “birthed mouths” and could speak Ihrimsû. They reminded Nin’janjin of Cu’jara-Cinmoi’s treachery. Seeking revenge, Nin’janjin and his warriors rose up in rebellion and joined the Inchoroi for the Battle of Pir Pahal, the first battle of the Cûno-Inchoroi Wars. However, upon seeing the shockingly horrific nature of their would-be allies, Nin’janjin’s warriors rebelled against him and instead joined Cû’jara-Cinmoi’s forces. The Inchoroi were overpowered and lost the resulting battle. However, when they fled back into the Incû-Holoinas, they took Nin’janjin with them.
Several years later, when Cû’jara-Cinmoi had grown old and frail, Nin’janjin emerged from the Ark asking to see him. Cû’jara-Cinmoi was astonished to see that his old enemy had not aged. Nin’janjin revealed that the Inchoroi knew the secrets of immortality. He agreed to grant the Inchoroi mercy in exchange for the gift of eternal life. However, the Inchoroi medications which granted immortality were a cursed gift - they gave rise to the Womb Plague which spread rapidly and killed all the women of Cûnuroi. Only the males survived, now a race without a future.
The Nonmen went to war against the Inchoroi, seeking vengeance for their dead wives and daughters, and for the eventual extinction of their race. The Battle of Pir Minginnial raged on the plain of the Inniür-Shigogli, and Nin’janjin turned against his old enemy Cû’jara-Cinmoi in the midst of the battlefield. And this time, when they fought, Nin’janjin killed him with a spear thrust.
Nin'janjin's fate is unclear: it is known that he spoke to Nil'giccas after his victory at the Battle of Isal’imial and told him about the Inverse Fire and the Golden Room at the heart of the Incû-Holoinas, resulting in Nil'giccas sending three explorers to investigate further. When two of them returned gibbering and raving, Nil'giccas put them to death on the advice of the third, Cet’ingira and abandoned the Ark, raising the Barricades about it. It is possible that Nil'giccas had Nin'janjin executed for his treachery.