Fans of K-pop idol EXO, dressed for the concert day -- white and navy -- lined up in front of the concert venue.
Thousands come hours before the show to get limited edition giveaway goodies produced by masters of fan sites called "hommas."
Hommas are ardent admirers who run sites or social network service accounts for fans of certain K-pop stars. The name "homma" is short for "homepage master," and they stand out from regular fans in that they actually play a role in marketing for their star's fame by uploading high-quality pictures and videos of K-pop stars.
Members of popular boy bands like EXO have scores of hommas.
"The biggest motivation for this work is to let others know how handsome my idol star is, and what a good singer and dancer he is," Estrella Kim, a clerical worker in Seoul who spends two to three hours each day after work photoshopping and editing, told ABC News. Kim, who has shared her pictures and videos of EXO on her Twitter account since 2013, explained that becoming a homma was "inevitable" because of her idol's charm.
To capture the split-second of eye contact or the natural glamour in everyday life, hommas follow stars and stake out spots to take pictures at all officially scheduled events -- concerts, airports, even commutes to broadcast stations.
Other fans appreciate hommas because their pictures portray affection that only most serious fans would notice.
"Hommas' photos and videos are focused on grabbing the fetching bits of an idol star, making them more attractive than the pictures taken by professional photographers," K-pop enthusiast Jiyun Choi, who spends at least an hour every day skimming hommas' Twitter accounts, told ABC News.
Some hommas go further, selling goods including calendars, photo books, tumblers and bumper stickers featuring exclusive photos. The profits are used to support the idols by sending food trucks, snacks for staff or even donations.
"When it is my idol's birthday or debut anniversary, I sell merchandise to pay for subway advertisement," Venus Lee, another homma who has managed her fan account on Twitter since 2015, told ABC News. "If the profit I made from selling merchandise isn't enough, I will use my own dime. When it turns out to be more than the targeted amount, I would save up for the next support event."
Hommas not only send support to idols, they also share a passion within the fan community. Kim gave out 3,000 plastic fans to EXO admirers during a concert last summer. Other hommas bring small bundle of snacks for fans who wait for long hours out in the sun. Hommas also hand out photo cards and slogans.
But not everyone is given the chance to get their hands on the goodies -- Hommas decide, weighing conditions including being a member of the official fan site, or to prove that they've streamed an artist's song at least 20 times.
Hommas, it should be noted, are different from the paparazzi that chase celebrities.
"Hommas do not follow around private schedules of a K-pop star," Kim explained. "Hommas' pictures are taken based on affection for each star and aim to do good for the celebrity, not to cause trouble by digging into their secrets."