Fannie is one of the protagonists in The Little Liar. She survives the Holocaust after being pushed off a train by Sebastian with the instruction to tell the world the truth about the events. Dedicated and loving, she forms important relationships and works to recount her experiences. She eventually focuses on finding Nico, staying with him to uncover the truth behind his lies.

Sebastian is a protagonist in The Little Liar, and Nico's older brother. Jealous of his brother and blaming him for his family's fate, he struggles with complex feelings during and after their time at Auschwitz. He later seeks justice against escaped Nazis but ultimately learns to forgive Nico.

Udo is the main antagonist in The Little Liar. A Nazi SS officer, he manipulates Nico into deceiving the Jewish community of Salonika. Promoted to a high-ranking position at Auschwitz, Udo is cruel and devoted to Nazi ideology. He is eventually captured as he tries to escape, but his pride and violent tendencies ultimately lead to his downfall.