Zero Requiem is a plan created by Lelouch and carried out with the assistance of Suzaku and possibly C.C. to end all war and to usher an age of peace. The plan involved focusing all of the world's hatred on Lelouch, then have Suzaku disguised as Zero kill him, dissipating the hatred and allowing the world to focus on more important matters than fighting, such as reconstruction and helping others, thus facilitating peace. Lelouch arranges the public execution of The Black Knights' leaders and the United Federation of Nations representatives. When Suzaku, disguised as Zero, interrupts and kills Lelouch, the culmination of the Zero Requiem as they had planned. By directing all the hatred of the world onto him, Lelouch's death will serve to facilitate peace. He dies smiling, saying he is the one who both destroys worlds and creates them. Suzaku is left to play the role of Zero. Nunnally can only watch in shock. When Lelouch falls near her, she takes his hand and realizes that he has sacrificed himself on purpose to bring world peace. Lelouch dies in the arms of a crying Nunnally, who then succeeds her brother as Empress of Britannia.
I had previously ordered a commission I requested from your website a Lelouch/Zero cosplay from the anime Code Geass. I loved the cosplay and was finally able to wear it at my local anime convention this past weekend.
*Also, the convention I attended with this cosplay is SacAnime in Sacramento, CA. USA