Karin Yuuki

Number 4 of UQ Holders immortal squad Numbers. She is very devoted to Yukihime after having been saved by her in the past and is jealous of Toutas close relationship with her. Her immortality is said to come from divine origin as all her wounds heal instantly instead of just regenerating fast like in most immortals. Because of it she was branded as a witch and hunted when she was a small child centuries ago. Source: Wikipedia