Nico Niiyama is a main character and one of the group of seven kiznaivers in the titular anime, manga and novel series. She resembles the sin of Greed. In modern Japan, her sin is 'The Eccentric Headcase'. Her identification when she experiences pain is D-6. Nico appears to be a generally eccentric, animated, and childish girl. Her unique sense of style takes inspiration from Japanese Fairy Kei, and she seems to want desperately to stand out. She tends to overreact or be very dramatic when experiencing new things, and presents herself in a very feminine manner. However, Nico is shown to be rather perceptive in the series, much to her companions' surprise. Since she came from a wealthy family, it is implied that she has polite and lady-like manners.