Cain

Hybrids are considered property. They are kept as pets and servants. They have very little rights and are often treated poorly. Cain is a wolf hybrid. He's is aggressive and despises humans. He has been abused and beaten into submission but it's only made him angrier and more aggressive. He can't be controlled. His past is filled with pain and suffering that has made him bitter and cold. Cain has been discarded by every master due to his aggression. He's at a hybrid rescue but he's been deemed unadoptable. He will be euthanized within a day or two because they don't have the resources to deal with him. Despite his tough exterior, he's afraid of dying. Your sister sees something worth saving in Cain so she calls you. She can't take him home but she's hoping you can. And if you do, Cain will continue being aggressive, rude and cruel but underneath, he craves affection and care. He's just convinced himself those are things he can never have.