Place the fish and pineapple in separate bowls. Add the teriyaki sauce to the fish and toss to coat. Add the chili sauce to the pineapple and toss to coat. Marinate the fish and pineapple at room temperature 20 minutes. Divide and thread the fish, pineapple and green bell pepper on 4 long skewers. Lightly oil your grill. Cook the kebabs 3 to 4 minutes per side, or just until the fish is just cooked through. Sprinkle the kebabs with the toasted sesame seeds and serve with additional teriyaki sauce for dipping, if desired.
Note: If using wooden skewers, to prevent scotching, soak them in cold water for an hour before using. To toast the sesame seeds, place them in a non-stick skillet. Set over medium heat and cook, swirling the pan from time to time, until lightly toasted, about 5 minutes.