Sayumi Morisaki 社崎沙弓

She's a member of a rival house of Rin Kamishiro and is the only class member who does not participate in the class's schemes. Her clan happens to be masters of unarmed combat, and though she does not take part in the long-standing feud between her family and Rin's, she does want to compete honorably with Rin to finally determine who is the best.