A werewolf, also known as a lycanthrope, is a human being who, upon the complete rising of the full moon, becomes a fearsome and deadly were-wolf. This condition is caused by infection with lycanthropy, also known as werewolfry. Werewolves appear in the form of a wolf but, there are distinctions between them and regular wolves.

A mixture of powdered silver and dittany applied to a fresh bite will seal the wound and allow the victim to live on as a werewolf, although tragic tales are told of knowing victims begging for death rather than becoming werewolves. The Wolfsbane Potion, invented by Damocles, allows the werewolf to keep their human mind during transformation.

A werewolf cannot choose whether or not to transform and will no longer remember who they are and would kill even their best friend given the opportunity once transformed. Despite this, they are able to recall everything they have experienced throughout their transformation upon reverting to their human form.