Put teriyaki sauce in a dish just large enough to hold pork tenderloin. Add meat, cover and refrigerate for 1 hour, turning several times. Drain tenderloin and pat dry. Spread Lilikoi syrup on a plate and roll meat in it. Spread sesame seeds on another plate and roll syruped tenderloin in them, coating well. Preheat oven to 400 degrees. In a roasting pan, bake pork tenderloin for 20 minutes or until no longer pink at the thickest part. Let stand for 5 minutes. Serve.