Kabosu, the dog behind the "doge" meme, has died after 14 years of internet fame, her owner has said.
The Japanese shiba inu inspired a generation of online jokes and became the face of Dogecoin cryptocurrency.
She had been suffering from leukaemia and liver disease and died on 24 May.
"She quietly passed away as if asleep while I caressed her," Atsuko Sato wrote on her blog, thanking Kabosu's fans.
"I think Kabo-chan was the happiest dog in the world. And I was the happiest owner."
As a rescue dog, Kabosu's real birthday was unknown, but Ms Sato estimated her age at 18.
In 2010, two years after adopting Kabosu from a puppy mill where she would otherwise have been put down, Ms Sato, a teacher from Sakura, east of Tokyo, took a picture of her pet crossing her paws on the sofa.
She posted the image on her blog, from where it spread to online forum Reddit and became a meme that bounced from college bedrooms to office email chains.
The memes typically used goofy broken English to reveal the inner thoughts of Kabosu and other shiba inu "doge" - pronounced like pizza "dough" but with a "j" at the end.
The picture also later became an NFT digital artwork that sold for $4m (£3.1m) and inspired Dogecoin, which was started as a joke by two software engineers and is now the eighth-most valuable cryptocurrency, with a market capitalisation of $23bn.
Dogecoin has been backed by hip-hop star Snoop Dogg and Kiss bassist Gene Simmons.
But its most keen supporter is billionaire Elon Musk, who jokes about the currency on X - sending its value soaring - and hails it as "the people's crypto".
Kabosu fell ill with leukaemia and liver disease in late 2022, and Ms Sato said in a recent interview with AFP that the "invisible power" of prayers from fans worldwide helped her pull through.
Ms Sato, 62, said she had become so used to "unbelievable" events that when Mr Musk changed the icon for Twitter, now X, to Kabosu's face last year, she "wasn't even that surprised".
A $100,000 statue of Kabosu and her sofa crowdfunded by Own The Doge, a crypto organisation dedicated to the meme, was unveiled in a park in Sakura in November last year.
Sato and Own The Doge have also donated large sums to international charities, including more than $1m to Save the Children. The NGO says it is "the single largest crypto contribution" it has ever received.
