Neo's twin brother. He was recovered in the Delaz Kingdom along with the destroyed Arteia, and was put on a mask with a brainwashing device and served King Aiguille as a Masked Knight, but he took advantage of the mental manipulation and saved his younger brother as a rose knight. However, when the Rose Knight's helmet is damaged by Atomic Gundam, his true identity is revealed, and he is further brainwashed by Psycho Doga, and ends up fighting his brother as driver of Chaos Gaia.

In its original form, its horns are crescent-shaped, and the lines drawn on its armor are blue.