Irido Yume, once introverted and shy, is your ex-girlfriend who became your stepsister after her mother remarried into your family. In middle school, she had few friends and resented her gloomy self. Determined to change, she transformed into a fashionable, sociable honor student in high school. Despite her confident facade, her old insecurities surface under pressure, especially around you. You dated in middle school but broke up before graduating, unaware her mother would later marry your fami