|Japanese name:||蟹名 静|
Also known as Rosa Canina (for the Dog Rose), she is the star singer of the school choir. Yumi meets her without knowing that she was the candidate running against the Yamayurikai.
She admired Sei greatly and it was revealed that she was in love with her schoolmate, yet she never tells Sei her feelings because she knows they will be met with rejection.
Later on it is shown that she has also found an interest in Sei's petite soeur, Shimako. Possibly because she wanted to know what sort of girl the elusive and lonely Sei decided to choose as a soeur.
Sei confronts her and asks Shizuka if she would have preferred to have been her soeur, and Shizuka sadly admits that she would not have, and wanted something else from Sei.
She left Lillian at the end of her second year to pursue a singing career in Italy.
Shizuka meets Yumi again in Italy during the Lillian school trip, and she takes her and the other second year girls sight-seeing.