Frankenstein presents many examples of the corruption of youthful innocence. The most obvious case of lost innocence involves Victor. A young man on the cusp of adulthood, Victor leaves for university with high hopes and lofty ambitions. He aims to explore "unknown powers" and enlighten all of humanity to the deepest "mysteries of creation," but his success and his pride brings an end to his innocence. He creates a monster that reflects back to him the many flaws inherent in his own species (an unquenchable thirst for love, a tendency toward violence, and a bloodthirsty need for justice and revenge) and in himself (prejudice based on appearance). And, in turn, Victor's cruel "un-innocent" behavior also destroys the monster's innocence.
Victor and the monster's losses of innocence ultimately lead to the deaths of William, Justine, Elizabeth, and Clerval, four characters whom the novel portrays as uniquely gentle, kind, and, above all, innocent. Through these murders, Shelley suggests that innocence is fleeting, and will always be either lost or destroyed by the harsh reality of human nature.