I will never understand the meaning of the washing machines behind her.
It's a K-Pop thing. Laundromats are a very popular location/feature for K-Pop music videos. No idea why, but they put it in POP/STARS for authentic K-Pop flavor.
I asked a friend about it because I was curious. Apparently most groups are owned by 5 or 6 companies, and they're very big on cost control, including reusing sets, and laundromats are pretty prominent in the sets used. Worth noting, they actually force the members to sign a debt contract. They don't actually make money until they pay it off.