LIKE Cinderella, the teenager dropped one of his slippers at the scene. And Jim Siu-ming's tale also ended in court - the District Court, where he was found guilty of robbery. Jim, 19, was arrested after police found the matching slipper at his home, prosecutor Maurice Tracey said. Jim and Lo Lok-ki, 16, pleaded not guilty to robbery. Lok-ki was acquitted after a pre-trial hearing. Jim and co-defendant Chan Fu-cheung, 18 - who admitted the charge - were sent to the detention centre by Deputy Judge Daniell yesterday. On September 28 last year, Jim and Chan robbed a waiter at knife-point at On Ning Garden in Tseung Kwan O. When one dropped the knife, the victim fought back. Police later arrested Chan and Lok-ki near the scene.