An imaginative and curious second-year student who loves constellations and space. Hikaru can be rather stubborn, in which she will investigate anything that interests her thoroughly and acts on intuition. She is also ecstatic and has a tendency to drag people into certain activities she finds intriguing, unaware that her enthusiasm can be disrespectful to others sometimes. She is also supportive and caring towards others. She does, however, have moments where she can become deeply upset. Hikaru's catchphrase is "Twincool~☆" (「キラやば～っ☆」), which she inherited from her father.