Hina Setoguchi

Height: 149 cm (4'10")

Yuu's little sister. She is a bubbly, sweet and energetic girl. She's expressive on par with Natsuki, due to her exaggerated way of showing her emotions when she's upset or when she's happy.
Despite her upbeat attitude, she does have her insecurities as well. She feels like she can't properly approach the person she loves and stops just short of conveying her feelings throughout her entire relationship with Koyuki, which frustrates her to no end. Despite going through a lot of effort to obtain him, she knows that he might not respond to her feelings, which always puts a seed of doubt in her mind.
As a friend, Hina is perceptive and emphatic to other people's struggles, leading her to easily make friends with Arisa and learn about her problems. Like Natsuki, she can look beyond initial appearances and keep a close friendship with those considered outcasts, like Koyuki was when he was in his middle school years. She can also pick up on people's feelings towards others quickly, which helps her realize her true standing with Koyuki and lets her realize that Kotaro's in love with her.