The youngest Advenna Avis immortal. His guardian Ferment tortured him to test the limits of immortality. Czeslaw manages to devour Ferment ending his suffering. Unfortunately he learns from Fermets memories that he was simply being tortured for Femets own selfsatisfaction. As a result Czeslaw becomes paranoid and trusts no one making it his mission to devour other immortals before they can devour him. In the 1930s it appears he cares little for the lives of others even requesting that a large group of people be killed so he could find an immortal among them. However after meeting Isaac and Miria and being forgiven by Maiza he stops hunting other immortals and moves in with Ennis and Firo.