What creature is Remus Lupin?

The story behind the answer

Remus Lupin is a werewolf, having been bitten as a child by Fenrir Greyback. He transforms at the full moon, though the Wolfsbane Potion (brewed by Snape) lets him keep his mind during transformations. As Defence Against the Dark Arts teacher in Prisoner of Azkaban, his struggles highlight the prejudice werewolves face in the wizarding world.

A handy memory hook: his Marauder nickname is “Moony,” and his friends became Animagi—Prongs (stag), Padfoot (dog), and Wormtail (rat)—to accompany him safely during full moons. This also helps separate terms: Lupin isn