Johan Liebert is a character from the anime and manga series "Monster". He is the titular "monster" and main antagonist of the series. Johan Liebert is the older twin brother of Nina Fortner. He is known for his extraordinary level of charisma and intelligence, which he uses to cruelly manipulate and corrupt others, often with no apparent end other than to cause suffering and destruction. Johan Liebert was shot in the head at a young age but saved from death by Dr. Tenma, and because of this, he is very grateful to Dr. Tenma. Johan Liebert has spent portions of his life in different places under different aliases. One of the themes of Monster is how individuals are capable of transforming into monsters, and Johan often acts as both a direct and indirect catalyst for this transformation.