Height: 175 cm
Sumika is in love with her best friend, Ushio. Much to Sumika's dismay, Ushio only likes cute girls. While the athletic, sarcastic and long-legged Sumika is just not cute. She wishes she were born the kind of girl one wants to protect, while being a little shorter and maintaining a little clumsiness, but it's a lost cause.
Sumika loves karate, but gave up practicing it formally because it was "uncute". She is prone to jealousy as she is forced to watch Ushio crush again and again on girls who cannot return a mutual feeling. Sumika always ends up patching up her broken heart as her feelings always end up unrequited. Despite her own feelings, Sumika wants Ushio to be happy and wishes her friend could find love, even if it's not with her.