The erstwhile royal family of Dumraon, in Buxar district of south-central Bihar will sue populist author Chetan Bhagat for defaming the family in his latest novel "Half Girlfriend". "In the novel, members of my family have been described as drunkards," said Yuvraj Chandra Vijay Singh of Dumraon, Wednesday. The people burned effigies of Bhagat and staged a demonstration against him.