Naka Kaburagi

An unpopular model whose face looks like a criminal's when she's nervous. She got rejected by her senpai who prefers Umi's charming smile. She is out to get the secret of Umi's smile and become a top model like Umi to get back at her senpai. Umi hits her, kicks her, and sexually harasses her but he's also so much more important to her than stopping her hundredth failures and not giving up. She grows close to Umi and starts to care for him after he accepts her for who she is. She falls in love with Umi later on.