Heart Shaker is a song by South Korean girl group TWICE, released in December 2017 as the title track of their reissued album Merry and Happy. Written as a bright dance-pop track about confessing feelings, it became known for its catchy chorus and energetic choreography, which fans recreated in dance covers and short-form videos. The hook translates easily to edits and reaction clips, keeping the song alive well beyond its original promotion period as a shorthand for confident, cheerful K-pop energy.