BTS is the Billboard Music Awards' Top Social Artist!
The boy band beat out Justin Bieber, Selena Gomez, Ariana Grande and Shawn Mendes in the fan-voted category, becoming the first K-pop group to win a Billboard Music Award.
EXCLUSIVE: BTS 'Cannot Believe' They're Nominated at Billboard Music Awards -- Watch How Excited They Are!
"We never expected that, but before [they announced it], cameras were in front of us, and we were like, 'Seriously?' Like, 'OK, OK.' But we heard the name and it's like, we're speechless," Rap Monster told ET's Cameron Mathison backstage. "We cannot say a word, it's crazy."
"[Fans have] been waiting on the red carpet and even so many fans are in the arena. It's crazy," said Rap Monster, who was joined by bandmates Jin, Suga, J-Hope, Jimin, V and Jungkook. "Thank you for shouting out for us, thank you for voting for us, thank you for waiting for us and everything, please."
The band also had a fan backstage, in Celine Dion's son, Rene-Charles Angelil.
"They're pretty good! I like them, yeah," the 16-year-old told ET before getting a picture with BTS. "I don't know [if my mom likes them], I'll have to ask her. I'm pretty sure she does though, she keeps up with new music."
RELATED: Billboard Music Awards 2017: The Complete Winners List
BTS gained a few more fans on Sunday. Here's all the times BTS stole our hearts at the Billboard Music Awards:
1. When they couldn't believe they were actually at the Billboard Music Awards:
2. When they got down to Nicki Minaj:
3. When they jammed out to The Chainsmokers:
4. When they got a hold of Miley Cyrus' "Malibu" balloons:
5. When they turned back time with Cher:
6. When their category came up and they weren't sure they were going to win, so they crossed their fingers for that extra juju:
7. When that juju worked and they got a standing ovation:
8. When Miley cheered after their big win:
9. When Halsey fangirled over them during the show:
10. When they met Camila Cabello backstage:
11. When they played it cool with Desiigner:
See more from the Billboard Music Awards in the video below.