St. Arcadia' headmistress and Reona's older sister. Ogiwara is her boyfriend. She had brought Takuro in to this school to give her sister the ultimate pleasure. In the fourth episode, Reina rapes Takuro and was given her desired "ultimate pleasure". Reina has unimaginable power and controls the school entirely. She runs a background lab to scan the school constantly with cameras and is willing to do anything it takes to give her younger sister Reona pleasure.