BTS’s RM and J-Hope are huge Billie Eilish fans.

The K-pop stars headed down to Eilish’s gig at Seoul’s Gocheok Sky Dome on Monday, sharing videos of themselves going crazy and dancing up a storm to some of the singer’s hits.

RM and J-Hope clearly caught the attention of some social media users, but they still danced like no one was watching, busting a move to songs, including “Bad Guy” and “You Should See Me In a Crown”.

The pair hung out with Eilish and her brother Finneas backstage, sharing photos on Instagram.

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They also showed off their “Happier Than Ever” tour wristbands.

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See some of the fan reaction to the duo’s moves below: