Brother?

It's the start of the rebellious acts of Zero. He has just saved Suzaku Kururugi, and made his big entrance along with the black knights. As the fighting ensues, a bystander running away has already discovered Zero's identity as Lelouch Lamperouge. How? Because he know's him from the past. The past in which they were brothers.

(COVER ART ISNT MINE: https://www.pinterest.com/hsara0308/ thats the original)

Disclaimer: Other than the main character, everything else comes from the series Code Geass: Lelouch of the Rebellion and has spoilers for said series