Kohei Hayasaka is a third-year university student taking up Engineering and the bassist and leader of Fujin RIZING!. The band leader who looks after everyone as the trusted senior member. She's been called "Ko-nee" since the group was small and it stuck. While usually a calm and kind person, she gets rather terrifying if she gets mad. She possesses extraordinary strength but avoids any and all household appliances due to her clumsy nature.