Kasumi Toyama is the energetic leader of Poppin'Party in BanG Dream, and kirakira dokidoki is her defining catchphrase, a shorthand for the sparkling, heart-pounding feeling she gets from music and new experiences. Fans adopted the phrase as a quick way to signal excitement, admiration, or a crush, and short clips of Kasumi saying it spread through anime edits, reaction videos, and soundboards. It remains popular because it packs her whole optimistic outlook into two playful Japanese words that are instantly recognisable to BanG Dream fans.