Place the chicken thighs in a bowl and coat them with half the teriyaki sauce. Add a pinch of salt and pepper, then let them sit for 10 minutes.
Preheat a grill or grill pan over medium heat and lightly oil the grates with the vegetable oil.
Grill the chicken for 5 to 6 minutes per side until it reaches an internal temperature of 165°F. Remove and let it rest for a few minutes before slicing.
While the chicken rests, grill the pineapple chunks for 2 to 3 minutes per side until they show light grill marks.
Bring a small pot of water to a boil, add the snap peas, and cook for 2 minutes. Drain and rinse under cold water to keep them crisp.
Divide the cooked rice among four bowls. Top each with sliced chicken, grilled pineapple, and snap peas.
Drizzle the remaining teriyaki sauce over the bowls and sprinkle with sesame seeds before serving.