Himeko Mashima is a supporting character in the anime series Show by Rock!!. She is the energetic and passionate drummer of the band Plasmagica. Known for her tomboyish personality and strong sense of loyalty to her friends, Himeko brings a lively and supportive presence to her group. Her dedication and upbeat attitude serve as inspiration to her bandmates, helping them overcome various challenges throughout their musical journey in the vibrant world of Midi City.