It’s been less than a day since STAYC‘s debut song “So Bad” was released, but the group is already smashing records. With over 4,300 sales, they have the highest first day debut sales record for any 2020 girl group. They’re also the only 2020 rookie girl group to debut on the Bugs real-time top 20 and the Genie real-time chart.

But many international fans had never heard of them before this week—so how did they get so big?

1. Their producers

While the most popular rookie groups typically come from major agencies, STAYC is actually the first group to debut under a brand new company—High Up Entertainment. A subsidiary of CJ E&M, High Up Entertainment was formed in 2017 by the legendary production duo Black Eyed Pilseung.

While you may not have heard of their name before, you’ve almost certain heard some of their songs. Members Rado and Choi Kyu Sung and the brains behind TWICE‘s “Likey”, “Cheer Up”, and “Fancy”,

Apink‘s “I’m So Sick”, “Eung Eung”, and “Dumhdurum”,

Chungha‘s “Rollercoaster” and “Gotta Go”,

and many more! With such renowned producers behind them, it’s no surprise that STAYC debuted with a certified bop in “So Bad”. The catchy track definitely helped propel them up the charts, as did their association with the famous production team.

2. Their famous members

STAYC’s producers aren’t the only ones who are already famous. Two of the members may also have their own following already because they used to be successful actresses.

The first is Sieun, STAYC’s main vocalist. Prior to joining the group, she was an actress and idol trainee under JYP Entertainment. Recently, she appeared on JTBC‘s Mystic Pop-Up Bar, SBS‘s Still 17, and more.

Another vocalist in the group (with a surprisingly similar name) was also an actress: Seeun. On top of that, Seeun used to be a trainee under Play M Entertainment, and was part of the pre-debut group that eventually became Weeekly.

3. A famous parent

There are also many people checking out STAYC’s debut because Sieun’s dad is famous, too. She’s the daughter of famous singer and former actor Park Nam Jung.

54-year-old Park Nam Jung debuted all the way back in 1988, and is known for inventing a dance craze called “the L dance” around the same time.

Currently under NJP Entertainment, he released a mini album and appeared on Singderella a few years ago. Now, Sieun is using her born talent to follow in his footsteps.

4. Their pre-debut videos

In the weeks before the group debuted, STAYC racked up millions of views with two innovative YouTube videos. The first was a vocal cover medley in which the members sang some of the biggest hit songs as if they came from other agencies. They turned Red Velvet‘s “Psycho”, for example, into a YG Entertainment-style bop, bringing in 1.6 million views to date.

The second was a dance cover medley, which currently sits at over 1.1 million views. Alongside tackling some of the most-loved choreographies, the STAYC members also cycled through some of the most popular school uniform looks in K-Pop history.

5. Talent, visuals, and adorable personalities

Last but not least, there’s no doubt that STAYC‘s talent, visuals, and personalities are a big part of their growing success. All the members are considered part of the group’s vocal line, which explains how great they sounded in “So Bad”.

On top of that, many early fans have noted how gorgeous the members are. It appears that 16-year-old maknae line member Yoon is considered the main visual, but every member has their own beautiful charms.

심자윤 토미에 그자체세요… #스테이씨 #STAYC #윤 pic.twitter.com/DNointTWJw

— 쿨이 (@040414Y) November 12, 2020

And on top of that, they’re already capturing viewers with their adorable personalities. One clip of STAYC’s precious rookie enthusiasm is attracting attention on the Korean side of Twitter with thousands of views and likes.

아 요 신인들 어떡함? ㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋ pic.twitter.com/h0hgRSANAa

— 세빌 (@segingah_) November 12, 2020

Watch the “So Bad” music video for yourself here!