An outrageous sexual act in which a man ejaculates onto a bowl of white rice. The female in this particular scenario then consumes the bowl of rice. Note the "Left-Hand" part of the title, which implies that the man is a right-handed self-fornicator using his least dominant hand.
Wilhelm: "Well, good day, Bentley, did you consummate with your lovely wife last evening?"
Bentley: "But of course, my dear Wilhelm. I finally got the unique opportunity to demonstrate the Left-Hand Suzuki Method to her. It was an experience I shan't soon forget."