Hiyoko's cute appearance, voice, and (initially) her way of talking give off the impression she is innocent and childlike. However, in her introduction alone, it is revealed that she is very direct and cruel with a side of malice. She squishes ants while telling Hajime Hinata that they make a satisfying popping noise if done correctly, and even invites him to join her. Later at the beach, she goes around trying to step on and trample the crabs, laughing as if it were just child's play.