Mix ground beef with sugar, soy sauce, and sake, then let it sit for a couple of minutes. Mince the garlic. Heat sesame oil in a wok over medium heat, add the garlic, and cook until fragrant. Add the ground beef and cook for a couple of minutes until browned.
Meanwhile, slice the green onions thinly on the diagonal. Lightly beat the eggs in a small bowl and set aside.
Add the steamed rice to the wok and stir-fry for a minute, then pour in the beaten eggs. Cook until the eggs are set and evenly dispersed. Add the green onions, season with salt and pepper to taste, and cook for another minute. Sprinkle sesame seeds, and serve with pickled red ginger.