She is the girl Randou likes and ironically, she liked him back before the accident, just she never told him. She has a quiet personality and feels responsible for what happened to her real twin sister Yuna after she ran away from home. Rina is a very emotional person and depends a lot on Randou (as Yuna) for support and guidance.
She is a very intelligent person and the smartest in her class, though she seems to struggle when it comes to cooking. After Randou came back as Yuna, Rina has become very scared that her sister will end up leaving her again and hangs out with her more often than not because of it.