11. Elfen Lied

Lucy is born with special powers and the government kidnaps her in order to perform inhumane experiments. And when she has the chance to escape, she violently murders her captors, but receives a blow to her head that reverts her to a childlike state. When two cousins decide to take her in, they find themselves in the middle of a conspiracy that threatens their lives. 

Lucy's initial escape at the beginning of the anime.

Lucy and Kouta have a complex relationship.