Age: 15
Height: 158 cm
A 15-years-old girl and Hiyori's best friend. She is the first person who encouraged Hiyori to become more sociable and start going again to school. Hiyori calls her Ri-chan. Her most notable feature are her red twintails. She is also a part of the archery club, and prefers a guy who "will not die even if an arrow pierces his heart." A extra side story reveals that Ritsuka was very popular with boys in middle school and wondered what it would be like to love someone and to have a boyfriend. A boy confesses to her and she goes to te fireworks festival with him. However he says something about Hiyori that Ritsuka finds rude and hits him on the face with her bag. She runs to Hiyori's house and says that right now Hiyori is the one she loves (implying it as friends)and says to Hiyori that if she ever falls in love, Hiyori will be the first to know.
(Source: Wikipedia)