Beware the Were Puppy (Pet Sitter)

Max loves animals but his sneezy, allergic sister means no family pets. He's so happy when he realizes he can be a pet sitter. But with every new job he takes on there's always something a bit odd about the pet owner, which he can never put his finger on initially. Witches, fairies, goblins, mermaids why can't he pet sit for an ordinary pet owner? Max has to pet sit for a cute young werepup, owned by a not-cute old wizard. Fang has a bit of an odd name but he seems cuddly enough. Max's main priority is to make sure he takes Fang on his walkies secretly as pets are not allowed in the wizard's apartment block. Max has everything under control until on one secret walk the clouds part and a full moon pops out...