Durarara!!

Synopsis

Shinra Kishitani, an unlicensed underground doctor, talks to the headless woman, whose name is revealed to be Celty Sturluson, about her day via chat room. In the past, Celty had first realized she was a dullahan when she lost her head at a cemetery atop a hill. She had traveled far and wide for the head, ending up in Ikebukuro. Celty learned from Izaya that an old street artist saw a dullahan missing its head. Celty quickly goes to find the artist, but cannot find him. Shizuo knows where the artist is and helps her talk to him. However, they find that the artist could not draw the head of the dullahan because he had no knowledge of its appearance. Shinra later tells Celty to give up looking for her head so they can live together forever, only to upset her and cause her to leave. Long ago, Shinra had first seen Celty as a child. His father, Shingen Kishitani had offered her a place to stay in exchange for being dissected. Her wounds and bruises had healed rapidly, recognizing her immortality. It is revealed that Shinra was the man that told the artist earlier that the dullahan was perfect without the head. (Source: Wikipedia)