Easter Eggers can have single combs. Easter Eggers are birds without any real breeding trait requirements, they just posses the dominate blue egg laying gene. Which, doesn't even mean that they will lay blue, or green eggs. However, not every poorly breed, or mixed breed fowl is an Easter Egger. Your cockerel shows no signs of Easter Egger blood. He is also not a Japanese bantam which would posses short legs, a sharper tail angle, and would be beardless.
Your rooster looks like a cute barnyard mutt. If he is a supposed pureblood chicken (hatchery pureblood doesn't actually mean the bird hasn't been crossed), then he is a very poor representation of his breed, whatever that may be.