>>114574606John Stewart is a harem anime protagonist. He's the straight man in the team dynamic and he has at least three super powered girls, two of them aliens and the other a shape shifter, lusting after him and being jealous of each other. His scenes revolve around him and his relationships, while he tries to focus on his duty as a superhero. Often the two will clash, like when his planet is invaded by his alien girlfriend. His scenes are generally action or romance/relationship comedy.
Personally, I liked the character. He's the same sort of role as Superman, a good leader type and his character arc appeals to those who like romance in their adventure stories. I'd say he's even closer to a Captain America-like character since he served with the military. He's got a classic American success story character background. Starts off a nerdy, comic loving kid. Mans up and joins the marines. Gets an education and becomes an architect. In the show, they depict him as someone who knows everyone in his neighborhood and everyone looks up to him because he's the man. He's the kid who decided to do right and work hard. He's just a wholesome character and yes, he's African-American.