Beyond the Story: BTS release memoir on Army Day

The highly anticipated book contains a chronological summary of the K-pop megastars' musical career

BTS released their memoir on July 9, 'Army Day'. All photos: AFP

The hotly anticipated book was released in South Korea to mark the band's 10th anniversary

The release date of the memoir is a nod to the day the megastars' loyal international fan base, known as the Army, came into being 10 years ago

Copies of the BTS memoir at a bookstore in Seoul

BTS fans Audrey, left, and Aqilah, who visited Seoul from Malaysia to purchase copies of the book on the day of its release

BTS fans wait for the opening of a bookstore in Seoul

The BTS memoir shot to the top of the Amazon and Barnes and Noble bestseller lists in May on the strength of its pre-orders

K-pop megastars BTS have released their hotly anticipated memoir in South Korea, marking their 10th anniversary as a group.

Beyond the Story: 10-Year Record of BTS is the septet's first official book and contains a chronological summary of their musical career as well as hints at their future endeavours, according to their agency Bighit Music.

Crowds were kept away by heavy rain on Sunday morning, but some diehard fans braved the weather to gather in front of the Kyobo bookstore in Gwanghwamun, one of the biggest in Seoul.

Sri Lankan fan Lakshi said that if her excitement were measured on a "one to 10 scale, then it is about a million".

Aqilah, a fan from Malaysia, said: "I came here since 9am and I finally got this book."

Malaysian BTS fans Audrey, left, and Aqilah at the Kyobo bookstore in Gwanghwamun, Seoul. AFP

The book shot to the top of the Amazon and Barnes and Noble bestseller lists in May on the strength of its pre-orders.

It was co-written by South Korean journalist Kang Myeong-seok and members of the band, according to its US publisher Flatiron Books.

The release date of the memoir, July 9, is a nod to a significant date in the septet's history. Called Army Day, it is the day the megastars' loyal international fan base, known as the Army, first came into being 10 years ago.

"[BTS] thank you for saving me when I needed it," said Audrey, another fan from Malaysia who scheduled a holiday in Seoul to coincide with the memoir's release.

"I wish I could say more, but I am going to cry now," she added.

Over the course of their decade in the limelight, BTS have become a global cultural phenomenon, selling out stadiums and dominating charts around the world while raking in billions for South Korea's economy.

The band are currently on hiatus, with members pursuing solo projects while two of the group complete South Korea's mandatory military service.

All able-bodied men in South Korea must serve at least 18 months in the military and, after a years-long debate about whether BTS deserved an exemption, Jin, the oldest member of the group, enlisted last year.

His bandmate J-Hope started his mandatory service in April, South Korean media reported at the time.

Before the hiatus, BTS bagged six No 1 hits on its Hot 100, Billboard said, and all seven members of the boy band have reached top spots in the chart with solo tracks.