Tachibana Miya

Protagonist's younger sister, who playfully calls her brother, "Nii-ni". She tends to be jealous when her brother is with another girl, with the exceptions of Sae, Ai and Rihoko, who are her close friends. Her favorite food is nikuman, which she frequently brings up in conversation, often completely out of context. She often wakes her brother up when it is time for school, though she wakes up earlier. She has a very distinctive laugh.