Nash's History
Early history
Nash and Pearl were born in 1935 to Susan Finney, a human who had intentionally bred with a demon, believing her children to be the next step in evolution. In 1940, at the age of five, the twins were schooled regularly by their mother about their greater purpose and taught to live up to it the best way they could.
In 1970, Nash and Pearl both followed their mother's plan and bred with demons themselves. All of their children were killed by monster-hunters however, among then Alasdair Coames. Their mother suggested to them that, instead of breeding with demons, they breed with humans possessing strong magic, since not being able to blend in made their children vulnerable.
At some point, Nash proposed marriage to Lavinia and Sophronia Fairweather to make them his dual-brides, but they stole his engagement ring, the Ring of Narcissus, and left.
Twilight
Many years later, Nash and Pearl were approached by the masked Twilight, who told them of his plans to create a new, evolved universe, which along with his promise of bloodshed made them agree to work for him. Under his leadership, they killed Nadira's squad of Slayers in the Azores.
Angel eventually reneged on the Twilight affair, and Nash and Pearl vowed revenge against him. During the end of magic, their mother was no longer able to mystically prolong her life, and she asked her children to kill her.
After Nash and Pearl massacred the patrons of a bar in London, Whistler informed them that the world didn't know it was dead yet and needed to evolve. The twins accepted Whistler's proposition for the sake of bringing in the next stage of evolution and getting payback on their old boss, something their mother had supported.
Working for Whistler
Attempting to find Angel, the three half-demons tracked him to the Giles residence, where they only found Lavinia and Sophronia, as Angel was currently in Quor'toth. Whistler informed the sisters that he intended to complete the ascension that Buffy and Angel had interrupted as part of a plan to save the world by evolving it to the next stage, and he told the aunts when and where Angel should meet him.
Later, the three half-demons concluded a pact with a living Eyghon the Sleepwalker to try and restore magic using accumulated magical artifacts to trigger a magic plague, with Whistler agreeing to give Eyghon control of Europe after magic had been restored, to rule as he sees fit. However, Eyghon didn't trust Nash and Pearl, conscious and afraid that they didn't want to share the power and would try to double-cross him.
When Alasdair's cloaking device for his magical items was shut down in an effort to help resurrect Giles, Whistler and his group quickly went after them. Nash and Pearl fought with Angel and Faith then escaped with the items.
With Giles resurrected, Angel and the others headed out to stop Whistler's plan.[6] In the ensuing confrontation on a rooftop in Hackney, Angel attempted to reason with Whistler, who still believed that he was saving the world and unleashed a magical plague, mutating the several people who had gathered to watch the fight.
Although their plan was working successfully, Nash was stabbed in the back by Nadira, who he had severely burned, and Faith finished killing him.
