THE GLOBAL K-Pop music craze is generating a fortune for Bang Si-hyuk, a South Korean producer known as “Hitman.”

Thanks to legions of fans obsessively devoted to boy band BTS, known collectively as the Army, the estimated value of his production company has soared, making him one of the biggest winners in the K-Pop boom. Mr. Bang, 46, is worth $770 million, according to the Bloomberg Billionaires Index.

The band — short for Bangtan Sonyeondan, which translates to Bulletproof Boy Scouts — sold out London’s 90,000-seat Wembley Stadium in 90 minutes earlier this year. The BTS members, all in their 20s, bond with fans by opening up about their anxieties and struggles through social media, which Bang called a “window into the soul of BTS.”

The producer and his Big Hit Entertainment Co. are riding a 20-year wave of popularity for a formula of highly choreographed, photogenic performers and synthesized beats. The industry that unleashed such hits as Psy’s “Gangnam Style” is now worth $5 billion, according to Korea Creative Content Agency.

DRIVING FORCE
“Bang’s focus on fan communications has become the biggest driving force of BTS’s popularity,” said Kwak Young-ho, co-founder at Hanteo Chart, which partners with Billboard on album sales data. “BTS has now become a platform.”

The mania has delivered sold-out concerts, No. 1 albums, billions of YouTube views and made the group’s seven members the world’s most tweeted-about celebrities. The band collaborated on Unicef’s anti-violence campaign, with the hit Love Yourself albums, and last year its members became the first K-Pop stars to address the United Nations.

Big Hit had weighed a potential initial public offering in 2017, but Bang said at the time that the company would need to become bigger and establish a more sustainable production system before making that move. The firm’s second-biggest investor, after Bang, is Netmarble Corp., a gaming company led by his cousin.

FEELS SURREAL
Mr. Bang’s stake representing 49% of Big Hit common shares was valued by the Bloomberg Billionaires Index using 2018 financials and price-to-earnings multiples of publicly traded industry peers SM Entertainment Co., JYP Entertainment Corp. and YG Entertainment, Inc.

Big Hit’s revenue more than doubled to 214 billion won ($187 million) in 2018, according to regulatory filings.

Bang and Big Hit declined to comment for this story.

“I’m happy, but at the same time it feels surreal,” Mr. Bang said of his success in a rare 2017 interview with Bloomberg.

A songwriter and fan of American hip-hop, Bang entered the music industry in his 20s and came up with a string of hits at JYP Entertainment, helping to set the foundation for K-Pop idol culture. Although the “Hitman” moniker was derived from his family name, Mr. Bang earned his reputation as a hit-maker and launched Big Hit in 2005.

NINTENDO TENNIS
He struggled initially, and the company edged toward bankruptcy in its early years. Business was sometimes so quiet that artists stopped by the office only to play tennis matches on Big Hit’s Nintendo Wii, he said in the interview.

While BTS remained insulated from a sex and corruption scandal that rocked the K-Pop world last month, the band had its own controversy in late 2018 when a T-shirt worn by one member sparked a furor in Japan.

As the band’s popularity surged, companies from Coca-Cola Co. to Puma SE and Hyundai Motor Co. have signed up the stars as brand ambassadors. In addition to Big Hit’s proprietary merchandise such as games and cushions to pajamas featuring characters created by BTS, there’s even a line of Barbie dolls.

Bang himself is a low-key figure not known for the ostentatious displays of wealth often seen in K-Pop. While known as something of a foodie, he was downing a $3 bowl of soup from a convenience store during the 2017 interview. Appearing as a mentor in an Idol-style television show, he bluntly scolded contestants for not trying hard enough.

The BTS whirlwind is now sweeping the US, with the band making its debut on Saturday Night Live this weekend and a May 1 appearance at the Billboard Music Awards in Las Vegas. It is also set to release a new album later this week.

In 2017, Mr. Bang was asked if Big Hit would make as much money with BTS as artists like Taylor Swift and Beyoncé.

“Yes,” he said. “Only if I make the right moves.” — Bloomberg

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