Combine the Black Japonica and wild rice together. Wash and drain thoroughly. Place in a medium sized pot together with 2 1/3 cups (560 ml) of water and sesame oil. Bring to a boil. Reduce heat and allow it to simmer for 40 to 45 minutes or until all water is absorbed and rice is tender. Place in a large bowl together with corn.
Boil edamame in lightly salted water for about 3 minutes. Drain and add to large bowl with wild rice and corn.
Combine all dressing ingredients in a small bowl. Pour over wild rice, corn, and edamame. Toss to combine.
Sprinkle green onions on the top.
Serve warm or at room temperature.