Demon Thief by Darren Shan

The protagonist of Demon Thief by Darren Shan is a boy named Cornelius. He has a baby brother called Art and two parents. There also is a group of demon hunters. The antagonist is the demon master Lord Loss. The story takes place approximately 30 years before Lord Loss takes place. The story takes place in a village called Paskington and in the world of the Demonata. In this story, Cornelius' brother is kidnapped by demons. Cornelius gets together with demons hunters to find his brother. Then Cornelius discovers that he has the power of creating portals between different worlds and uses this power to find his brother. Then he discovers that his brother is really a demon, servant of Lord Loss. A long time before, Cornelius had by accident opened a portal and had unconsciously stolen the demon. So at the end he discovers that he himself is the Demon thief.

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