Amu Chara: Dia

Diamond (ダイヤ)
Diamond is Amu's fourth Guardian Character. She becomes an X Egg when Amu dislikes all the changes that were happening in the spring. While Utau collecting X-eggs with Yukari, Utau finds Diamond's egg inside the box. She soon hatches into a X-character. Unusually, she is not shaped like the usual X-character. She looks like a normal Guardian Character but she has a black X-shaped clip covering her yellow diamond-shaped clip. Because of this, Amu doesn't know Diamond's true name. In the Japanese manga, Diamond's name is shorted to Dia. Diamond can Character Transform with Utau, becoming Dark Jewel, but however, the transformation does not last very long. When Amu finally is able to purify Diamond, they undergo a Character Transformation, becoming Amulet Diamond. Afterward, Diamond returns to her egg until she sees that Amu "shines again". In the anime television series.Diamond voiced by Kanae Ito.