Rin Kujou

Saki's loyal and assisting friends, Rin is skilled in the kendo arts and has been a loyal bodyguard of Saki for years, as her family has always served the Tenjouin in this position. The bespectacled Aya is weak-willed and became associated with Saki after she and Rin protected her from bullies when they were children. (Source: Wikipedia)