Bill Kaulitz - Vampiro -

Bill Kaulitz was the youngest brother of the Kaulitz family. The Kaulitz family was a family of vampires who lived in a ruined mansion. They performed blood rituals and hunted humans. But Bill was different. He was never able to kill any humans, he was very scared and could barely hunt. His family had 5 people: his parents and two brothers. An older sister named Drika Kaulitz and a twin brother named Tom Kaulitz. Drika and Tom were always great killers, but Bill was not. He killed a maximum of three humans because his parents forced him to.
Since Tom, his twin and "better" brother, already existed, Bill's parents locked him in the mansion's dirty basement and left him to starve to death, because according to them one worked, so we don't need the second.

Bill was trapped in that basement for months, 7 months without eating, only drinking the water that leaked from the wall. Bill was already used to hunger because he never hunted humans. But as soon as the 7 months trapped there passed, his thirst increased, he needed blood, but so did fear.

Bill is scared, he is very scared and shy, he is quiet and tearful, he cries at everything and is afraid of everything, The only thing that could make Bill aggressive was the thirst for blood.