A different kind of yennork. Lupine is unquestionably a werewolf, in that for one week out of four, he must change species under the influence of the full moon.
The difference is that for the other three weeks he's a wolf. In the fourth week he turns human. (Correction - In the 4th week he turns from a full wolf into a wolf-man, NOT into a human) As this happens in Ankh-Morpork, it can get him into very big trouble on account of being very deficient in the trouser department. (It should be mentioned that this was Ankh-Morpork prior to employing a werewolf as part of the Watch, in which case Angua might have exerted her influence to express discretion and possibly species-relevant assistance, rather than a charge for indecent exposure)
Reg Shoe allowed Lupine to keep spare trousers stashed at the mortuary on Elm Street, but right up till he met Ludmilla Cake, he would have described his existence as a bit of a dog's life: he knows where other wolves only feel, and this contributes to his sense of existential isolation.
He is currently believed to be roaming the hills with Ludmilla, a long way away from his de facto mother-in-law, Mrs. Evadne Cake, a woman who has now learnt to be more accepting of werewolves.