Klaus Mikaelson

Niklaus Mikaelson (a.k.a. Nik or Klaus) is an Original/hybird, and the son of an unnamed werewolf and Esther. He has six half-siblings: a deceased unnamed older half brother, four other half-brothers named Elijah, Finn, Kol, and Henrik, and a younger half-sister named Rebekah. Klaus is also the step-son of Mikael, with whom he had a strained relationship.
 * 2049_448759915166410_1384140956_n.jpg -  10th century
 * Turned -   ?
 * Species - Original vampire/hybird
 * Gender - male
 * Family - Rebkah Half sister
 * Elijah - half brother
 * kol - half brother
 * finn - half brother
 * esther - mother
 * mikael - step father
 * henrik - half brother
 * baby (with hayley)

He is first mentioned in a conversation between rose and stefan when she warns him about the Originals. She tells him that Klaus is believed to be the most hated and feared of all the Originals and those who fear him are desperate for his approval. Over the centuries, Klaus has become a recluse who confides in and trusts only the few members of his inner circle.