Step 1: Set up the grill for direct grilling and preheat to high.
Step 2: Snap off the woody bases of the asparagus and discard. Skewer 4 or 5 asparagus spears together (raft-like), using toothpicks or bamboo skewers.
Step 3: In a small bowl, combine the sesame oil, soy sauce, and garlic and stir with a fork to mix. Brush this mixture on the asparagus rafts on both sides. Season the asparagus with a little salt and lots of pepper.
Step 4: When ready to cook, place the asparagus rafts on the hot grill grate and grill until nicely browned on both sides, 2 to 4 minutes per side. Sprinkle the asparagus rafts with the sesame seeds as they grill. You can serve the asparagus as rafts or unskewer them before serving.