Moony, Wormtail, Padfoot and Prongs roam Hogwarts by moonlight much as they do by day: as four young men from the same house, the same year, the same room. Their very compatibility (mis)leads one to think that they are four of a kind. In the respects just listed, they are. Actually - essentially - they are not. For all that they can all change shape, three do so at will, and one most emphatically cannot. Three, in other words, are Beings - humans with Free Will and a sense of their own power, freedom and legal rights. The other is Beast, the werewolf, who shifts without will, by the mechanisms of something that has no will (the moon), at the behest of another beast who bites and transmits not only the disease of lycanthropy but the helplessness that accompanies the beast's power to destroy. The werewolf is a site of paradox: power and helplessness, a human life lived more consciously and with more sense of consequence but with less ability for self-determination because of his affliction and the laws which constrict him still further.
Remus Lupin's lycanthropy, this paper argues, stands in sharp contrast to his friends' Animagicity. As a character, Remus explores the paradox of being and being beast, of free will to transform and contagious destiny to transform. Moreover, his destiny to be constrained spills over into other questions of destiny and free will, such that Remus' likeness to Harry becomes ever more acute: Harry is marked as Remus is, lives with destiny as Remus does, is "contagious" as Remus is. Harry also walks the frontiers of his own theriomorphism, walks between his father's stag-self and Voldemort's snake. Remus, then, as the only parental friend left standing, teaches Harry how to live with destiny, how to define freedom and will not as an unhampered exercise of the individual, but as the exercise of choice - for the benefit of community - when essential choices are not permitted. Remus as Beast is the symptomatic point (in Zizek's sense) of the Wizarding world: the thing which must be suppressed so that the world can define itself. Similarly, his lycanthropy is the symptomatic point for Remus as Being - the thing which defines him as also essentially not that which he is defined to be. This is the free will Remus exercises: he lives his humanity very consciously, as he controls his contagion himself. Free will for Remus is not about individual agency to shape one's own life; it is about living with what cannot be changed.