Sir Dash is a new and mysterious character from the manga Code Geass: Shikkoku no Renya and he seems to be the antagonist of the series, although his intentions remain unknown.
His appearance is exactly like Lelouch but with much longer hair, a bit more slanted eyes, and is seemingly older. His eyes are purple, and his hair is black. He normally is seen wearing an elegant armor from his own.
Normally he is seen to be a very calm person, who usually sits and read his book. He reveals that he doesn't like fighting, and prefers that his comrades get along with each other. Most of the time, he is indifferent towards his allies, and he rarely shows any emotion. So far, he is interested in both Claire le Britannia and her pendant for unknown reasons. He considers Renya, C.C., Andreas and the others as enemies.
He was briefly shown with the geass in both of his eyes when Renya was gaining the curse, later on, he was mentioned by C.C. , in which she said to herself that he was getting 'serious'. He is firstly seen checking an old painting which shows Claire 's pendant, which indicates that he is searching for it. Later on, in an unknown castle, he is seen sitting and reading his book, while he talks to his comrades about the being who moves along with the princess, and how to get rid of it. He reveals that he doesn't like fighting.
It's shown in chapter 13, that he has killed Angie 's father some years ago.
Source: CodeGeass Wiki