Since this is Japan I can only conclude a few things. This man spent hours watching Stevie perform with an eye for detail and none for enjoyment of the music. He probably started a newsletter concerning the various stages of Stevie's eyewear choice and hairstyles. He knows trivia about Stevie's life that would stump Wonder's own mother. He has no idea what the words he's singing mean, and he doesn't care beyond that he forms the sounds sufficiently well. He more than likely has never met an actual black person.