Had an FO on a PVG layover go to his room, never to be seen again. Next day, the hotel staff opened his room door when he didn't show up for report time and saw a note with his uniform on the bed. Note said, "*******U (Insert CP name)". Called the CP and told him the FO was missing, but a note was found. He was adement, "what does it say"? "Well, it's addressed to you, and it says, Go ******* yourself". There was silence, and then I was transferred to crew scheduling for a layover extension. In the end it was found that he had hoped a one-way flight back home and abandoned the jet in PVG.