The "definitive" version of the Code Geass manga. Set when Lelouch and Suzuku begin the Zero Requiem Plan.

From Tokyopop:
Yuuichi Tate is overjoyed: He gets to go to a brand new high school. Of course, then he just happens to find out the school he choose is under frequent attack by strange creatures called ''Orphans'', and the school set up a special task force of female members called ''HiME''s, using various elements as their powers, to battle these invaders. That's not all, though. Each member of the HiME task force has their own, unique ''Key'', another person whom, upon being discovered, can team up with the HiME to create a ''Child'', a combative unit specifically needed to effectively battle these Orphans. And with Yuuichi's luck, he just happens to find out he's not just the ''Key'' for one of the HiMEs, but for two... Two highly competitive, rival schoolgirls. And that's only the start of the trouble.

Lelouch, Suzaku and other young warriors battle in the late Tokugawa Shogunate era, where the power of Geass forced Japan to falsely open up their ports!!

The curtain rises on an alternate world tale of Code Geass!!

(Taken from Bandai Entertainment)

The story takes place in the same official Code Geass history as the anime, but in a different era. The title character, Renya, is a 17-year-old boy with a mechanical left arm and shuriken throwing stars as his weapons of choice. The story begins when Renya encounters a mysterious, perpetually young witch named "Reifuu C.C." C.C. has appeared in Japan's historical Edo era to seek a new partner for a covenant. Meanwhile, a mysterious man, with a striking resemblance to the character Lelouch of the original anime, also appears with unknown intentions.

Iori Shijima, an ordinary high school student blessed with a good, common life. He has a cute childhood friend, lots of friends he can rely on, and a nice and beautiful mother. Additionally, his grades are good and he has a solid future plan. However, one day "transcendent beings" called ĀTRAIL appear on Earth, and Iori's everyday live crumbles as he learns about the secrets of another world and the meaning to his own existence.