Base on how I understand the Story Hell Girl Exist when she wish for life extension the reason she want to revenge the people who hurt her and the reason of her death.
Well, Enma Ai exist for more than 400 years as a Hell Girl. She was 13 years old when she suffer into bullying of other kids but only her cousin Sentarou .They became friends and turns into special treatment that becames romantic. They went into near falls together with the cherry blossoms. Many year past people are suffering from poverty and they thought Enma is the reason that's why they keep on finding Enma untill suck time they found out that Sentarou is hiding Enma Ai in the near-fall with cherry blossoms. They went next to Sentarou during his visit to Enma and became the reason of Enma caught by them.
They killed Enma's parents with blind fold and lastly Enma. They put Enma in grave without even killing her then they asked Sentarou to be the first to cover soil for Enma.
That is the story behind everything, Enma Became a Hell Girl
