Hastur has the appearance of a bipedal lizard with tentacles. Hastur's Sacred Artifact is the tentacles growing from his body. Anything that touches their ends gets stamped with a biohazard mark called the Yellow Seal and fall under the control of his ability. He actually has an irrepressible love for humans, but it is this trait that causes him to intimidate them away from the danger he poses.
He has a daring outfit, tight and showy clothes, has both hands half pink with tentacles.