時雨先輩の運命の人

A plain-looking high school girl named Nae feels inferior to her talented and beautiful older sister. She enters high school determined to become independent and handle things on her own. Early on, she encounters the strikingly handsome third-year senior named Shigure after he helps her with a lost item. Nae develops feelings for the sharp-tongued but kind Shigure. She learns that he harbors feelings for someone else, specifically connected to her sister. (Unreviewed summary by Grok 4.1)