Dr. Feel Good by girl group Rania (라니아), as requested by Lena.
As I was watching the video I was thinking that they couldn’t have been allowed to use that choreography on the music shows, considering that 4Minute had to alter their Mirror Mirror dance, which had the same “spread legs” move. Turns out they weren’t . I had to look it up, and Rania debuted with this song a little over a week after 4Minute came back with Mirror Mirror. Good thing they had 4Minute “test drive” the move, so they could tone it down a little. They were still criticised for being too provocative, though.