S01E03 — Cynthia and Grace

Taro says says, "Hello" to Cynthia in the hallway, but to his surprise, not only does she speak to him for the first time, she acts bitterly toward Taro. He soon learns that Cynthia was a child prodigy, but her gift caused her parents to split up, and she soon created a different Cynthia named, Grace, who holds all the bad memories of Cynthia's childhood. From time to time Cynthia lets Grace take over and work with the Hanaukyo computer system and other technical advances in the house.