Mayu is a homeless girl from the anime/manga series Elfen Lied, aged 12 to 13 in the manga and 13 to 14 in the anime. She is introduced when she goes to the inn that Kouta, Yuka and Nyuu live in to return an umbrella she found at her home. Her "home" refers to the beach that she lives on with a stray puppy she calls Wanta. They live off bread crusts from a nearby bakery, but when the bakery closes she hesitantly moves into the inn.

Mayu had run away from home after having to put up with repeated sexual abuse from her stepfather. Her mother did nothing to stop it because she was jealous of Mayu.

Kouta and Yuka eventually contact Mayu's mother asking to adopt the child - her mother is eager to follow through on this. They officially adopt Mayu and she begins to go to school.

She is voiced by Emiko Hagiwara in the Japanese anime, and by Cynthia Martinez in the English.

Elfen Lied?

Elfen Lied is an animanga series by Lynn Okamoto. The manga was composed of 12 volumes, and the anime was composed of 13 episodes and an OVA. The title is German for "Elves' Song" or "Song of the Elves". The name is taken from Eduard Mörike's poem, Elfenlied.

Elfen Lied revolves around the interactions, views, emotions, and discrimination between humans and the diclonius, a mutant species similar to humans in build but distinguishable by two cat-ear-like horns and "vectors", transparent arms which can pass through air and objects at high speed. The series is centered around the teenage Diclonius girl "Lucy", said to be the first Diclonius, being rejected by humans and her subsquent murderous vengance upon them.
~ Wikipedia