3x21 - Hell Girl

Yuzuki believes she can escape her fate of becoming the next Hell Girl as Tsugumi had. She meets a young boy named Kaito, who is being abused by his stepmother Nanami. Nanami used to treat Kaito with love; however, ever since she became pregnant with a girl she names Mao, Nanami begins to fawn over her and unreasonably punish Kaito. Kaito only desires to return to those earlier days of happiness when Nanami was much kinder. Yuzuki is shocked to realize that Kaito's father is aware of the domestic violence against his son, but refuses to acknowledge it. Believing his son is in the way of their family's happiness, he almost kills Kaito; however, he comes to his senses when Kaito sends Mao to Hell, and Nanami also returns to her old, kind self.