Seoul sensation: Meet the Korean cult rapper who's bigger than Bieber

He has been signed by Justin Bieber's manager, has the most "liked" video in YouTube history and yesterday shot up to No 3 in the UK singles chart. But who is Psy, the South Korean rapper conquering the world's dancefloors?

As of yesterday, the video to "Gangnam Style", in which Psy demonstrates the "giddy-up" dance that will no doubt soon be standard fare at Christmas parties, had picked up 251 million views on YouTube. It has also been "liked" 2,500,660 times – more than any other video in the website's history and one million more than Bieber's best effort. Psy, real name Park Jae Sang, is the latest export from South Korea's K-Pop (or Korean Pop) culture, whose usual exponents come in the form of auto-tuned, implausibly attractive girl and boy bands. Their videos regularly go viral among millions of teenagers at home and abroad, but Psy – a portly, thirtysomething rapper with a penchant for bow ties – has eclipsed them all, to the surprise and delight of K-pop's ex-pat fans.

"I am astounded that it's Psy that has done it," said Mimi Anim, 24, a journalist for the London Korean Times. "South Koreans in the UK are feeling quite proud that this short, chubby guy, who is not in the typical image of a Korean pop star, has cracked the UK and American charts. It is helping South Korean culture's presence abroad to grow."

With "Gangnam Style" topping the iTunes chart in nine countries and a string of high-profile television appearances behind him, Psy could quickly become the world's most famous South Korean. He has already been signed by Justin Bieber's manager, Scooter Braun.

"I don't know why Scooter wanted me," Psy told the American music channel, Fuse.

"For all us Koreans, it is a dream to break the American market with songs in our own language. It's going to be history for my country if I can."

Yesterday, he narrowly missed out on the UK No 1 slot but with sales showing no signs of slowing, "Gangnam Style" could yet reach the top. What most fans have not picked up on, however, is the subtext of what it means to be "Gangnam-style".

Gangnam – a wealthy district of the South Korean capital, Seoul – is home to the rich and privileged children of corporate millionaires.

So while fans love the kitsch video and Psy's "riding an invisible horse" dance, the song could, in fact, be a send-up of the rampant materialism of the Korean upper classes.