Nanaka Yatsushiro

Main heroine of the series. Nanaka is one of Sana's friends, and seemed to have feelings for Sana. When Sana returns to town after five years, her personality has completely changed from sweet and caring to a cold demeanor, and moody. When she meets Sana again after he returned she slaps him for apparently not knowing who she was. She still seems to have romantic feeling as she gets jealous whenever Sana is with another girl (especially Asami). (Source: Wikipedia)