A-JAX released a practice video through their official YouTube channel, showing member Seungjin diligently practicing for his performance of Girl's Day's "Something" for 'Show! �Music Core's 400th episode special�that took place over the past weekend.

As a part of the project group Boy's Day, Seungjin spared no efforts in perfecting the dance moves. �Even in a long skirt and heels, he seemed to have no trouble keeping his balance. He barely seemed distracted as other members smiled and recorded him on their phones, either.

How did you like Boy's Day's performance?

SEE ALSO: Performances from March 8th 'Show! Music Core' 400th episode special!