THE public only sees the glitz and the glamour, but as Pig-dog will tell you, this show business lark is nothing but hard work. The mutt of indeterminate breeding has long been a fixture in the area outside the O'Brien Road MTR entrance in Wan Chai - probably because her enormous girth reduces movement to a less-than-dignified shuffle, with propulsion coming mainly from her backside. The members of HUH!? - Hongkong's up-and-coming rock band - decided her hang-dog expression was just the sort of thing they wanted for the cover of their debut CD, What a Drag. Manager Jon Powter said cryptically: ''They felt they could identify with the dog - they feel a little like the dog must feel - a little bit outcast from the rest of life in Hongkong.'' Now Pig-dog finds she is spending much of her time being pointed at, prodded and made to pose for photographers. When P.S. caught up with Pig-dog she would only reluctantly be prodded from her lair, which she shares with her owner, street-sleeper Ah-chan. There was barely time to scratch before Ah-chan poured a bucket of cold water over her back as a sort of canine equivalent of going to the make-up room. A quick run through her less-than-sleek coat and it was time for lights, camera, action with the guys from HUH!? - singer Tim Leung, guitarist Edmund Leung, bassist Ian Lee and drummer Ming. The band declined a request to pat Pig-dog on the grounds that she would take a chunk out of their hands. It seems even four-legged mega-stars can be prone to temperamental outbursts.