This will be the last "chapter" I'll post. I'll be updating this page from time to time if any new questions come up, but if not, thanks again for reading.
Guibin: Nunnally did receive a Geass from C.C. in exchange for the promise that she'd allow C.C. to see Lelouch in a few years after he ceased to be a threat. The Geass was probably similar to the one she received in Nightmare of Nunnally, which allowed her to see the future.
Anonymous (Re: The "Nunners" Question): 'Nunners' was an affectionate fan nickname for Lelouch's sister that I chose to use because it showed a type of easy camaraderie between Lelouch and Nunnally that never existed in the original series. In canon, Lelouch handled his sister like porcelain—incredibly gently, for fear of hurting her. Since Galton's Children Nunnally grew up without injuries, Lelouch and Nunnally could banter and joke with each other more easily. I suspect that Lelouch teased her with "Nunners" when they were both children, but the nickname stuck and acquired more emotional depth as they grew older. And you're right: Lelouch certainly respected Nunnally's abilities, and loved her very much.
Zerole the Untamed: Nope, you didn't just imagine the C.C. x Lelouch hints…
This Is My Name: As requested, the final list…
Lelouch – Died of natural causes in his late nineties, seventy years after bringing down the Chinese Empire. Democratized most of the world before his death, albeit bloodily.
Suzaku– Reconciled with Lelouch several years after their failed (second) Requiem. Helped bring down the Chinese Empire, and remained in touch with Lelouch thereafter. Died in obscurity in his seventies, of natural causes. Nunnally and Lelouch both attended the funeral.
C.C. – Imprisoned by Nunnally until a few months before Lelouch's death. Died when she gave Nunnally her Code.
Nunnally – Lived another fifty-seven years. She left the world a united republic under the U.F.N. before joining her brother in the Collective Unconscious.
Kallen – Died during the Second Sino-Japanese war. Her efforts ended China's brief civil war.
Rolo – Splattered by Nana, Chapter 14
Arthur – Decapitated by Lucy, Chapter 6
Milly – Married and had children. Died of natural causes.
Rivalz – Killed in a subway bombing, Chapter 12
Nina Einstein – Lived to a ripe old age. Unfortunately.
Shirley – Married Lelouch. Died of natural causes.
Sayoko – Killed by Jeremiah, Chapter 10
Ohgi – Sent on a suicide mission by Lucy, Chapter 12
Minami – Purged by Lucy, Chapter 15
Sugiyama – Purged by Lucy, Chapter 15
Tamaki – Purged by Lucy, Chapter 15
Yoshida – Purged by Lucy, Chapter 15
Inoue – Purged by Lucy, Chapter 15
Tohdoh – Executed by Britannians, Chapter 12
Asahina – Executed by Britannians, Chapter 7
Chiba – Executed by Britannians, Chapter 7
Senba – Executed by Britannians, Chapter 7
Urabe – Executed by Britannians, Chapter 7
Taizo Kirihara – Killed during Cornelia's counterinsurgency
Futaba – Purged by Lucy, Chapter 15
Hinata – Purged by Lucy, Chapter 15
Minase – Purged by Lucy, Chapter 15
Kagesaki – Purged by Lucy, Chapter 15
Kaguya – Married and had children. Died of natural causes.
Rakshata – Locked in a Chinese prison camp after trying to liberate India. After Lelouch's "Cultural Revolution" ten years after Nunnally's accession, her whereabouts are unknown.
Diethard – Killed by Rolo, Chapter 14
Charles zi (di) Britannia – Died in the Thought Elevator, Chapter 24. Since he wasn't wiped out of existence, Lelouch is in for a very unpleasant family reunion when he enters the Collective Unconscious.
Marianne – Ditto.
Odysseus – Killed by Lucy, Chapter 15
Guinevere – Killed by Lucy, Chapter 15
Euphemia – Killed by Lucy, Chapter 15
Carline – Killed by Lucy, Chapter 15 (I'm starting to sense a pattern…)
Schneizel – Also lived to a ripe old age. I don't envy the guy…
Clovis – Killed by Lelouch via mind-control suicide, Chapter 12
Bismarck – Killed by Lucy, Chapter 25
Gino -- Killed by Lucy, Chapter 25
Dorothea – Killed by Lucy, Chapter 25 (I'm seriously considering copying-and-pasting "killed by Lucy" for the remainder of this list…)
Anya – SURVIVED!!!!!!!!!! (Well, died of natural causes years later like Milly and Kaguya. That counts, I guess…)
Nonette -- Killed by Lucy, Chapter 25
Luciano -- Killed by Lucy, Chapter 25. And good riddance.
Monica -- Killed by Lucy, Chapter 25
Bartley -- Killed by Lucy, Chapter 15
Darlton -- Killed by Lucy, Chapter 15
Jeremiah – Became a go-between for Lelouch and Nunnally. Managed to get them together from time to time. Died of natural causes.
Guilford -- Killed by Lucy, Chapter 15
The Glaston Knights -- Killed by Lucy, Chapter 15
Kanon – Survived, incredibly enough.
Villetta – Killed by Sayoko, Chapter 10
Kewell – Killed by Jeremiah, Chapter 5
Lloyd – Killed by Lelouch, Chapter 12
Cecile Croomy – Survived. Did not marry or have children. Died of natural causes.
V.V. – Floating in a vat somewhere under Alamogordo. Unearthed thousands of years later in an archaeological dig…
Alicia Lohmeyer – Incredibly, Nunnally's racist, xenophobic guardian escaped my notice. Not anymore! Hit by a bus shortly after Lelouch's coup failed.
Le Xingke – Executed for his brutal response to the Chinese Democracy Movement. Buried beside his beloved Empress.
Tianzi – As above.
The Eunuchs – Like Le and Tianzi, the Eunuchs were executed by China's new democratic rulers.
Hong Gu and Zhou Xianglin – Imprisoned for their roles in the Tiananmen Massacre. Not high profile enough to bother executing.
Mao – Killed by Suzaku, Chapter 20
Lucy – Survived. Still very young when Lelouch died, in Diclonius years. Published Lelouch's memoirs, much to Nunnally's chagrin, and then faded into obscurity. Nunnally was unable to locate her.
Kohta – Last spotted in Chapter 6. Probably emigrated with Yuuka and survived.
Yuuka – See above.
Mayu – May (or may not) have been executed by the Black Knights for turning in her stepfather, Chapter 19
Nana – MAYBE killed by Jeremiah, Chapter 23. I prefer to think that her freaky recuperative abilities got her out of it, since she was far from the blast radius, and...
…Actually, you know what? Yes. Nana survived. Somehow—I don't care how—she survived the blast, received Rakshata's antidote courtesy of Lelouch's Imperial Decree #1, and was adopted by a nurturing family that loved her. Screw cynicism.
Kurama – Delivered to Lucy's custody, Chapter 29. Take a wild guess what happens.
Bando – Killed by Nana, Chapter 11
Mariko – Killed by Lelouch's bombers, Chapter 23
Director Kakuzawa and his son – Executed for treason, Chapter 11
Nightwing of the Azure Shadow – Yep, Britannian medical technology is truly impressive...
Fellow Sufferer – Yes, Lucy ended up with the short end of the stick. On the bright side, she had over seventy years with Lelouch and Shirley (she visited more often after Kallen died), which is a LOT more than she got in canon. I also fear for the next would-be dictator after Nunnally dies, considering that Zero is still in the shadows somewhere…
EL x CG Fan – I assumed that Lucy's vectors (which I did know were invisible arms) were a type of telekinesis, since she can apparently summon and dismiss them at will and make them move through solid objects. Sorry you didn't like the epilogues, and thank you for your honesty.
Green Cloud: I tried to restrain most of Nunnally's OOC moments until the epilogues, when decades of ruling an empire destroyed her remaining naiveté. I always thought that canon Lelouch gave Nunnally the short end of the stick when he thrust an unprepared, emotionally and physically crippled girl onto the throne. At least Galton's Children's version of Nunnally went into her new job with both eyes open…no pun intended.
As to the world chess championship, it passed from Morphy to Zukertort (Steinitz retired a frustrated man after Morphy destroyed him). After a brief sojourn in Europe, the title returned to Britannia when Pillsbury crushed Zukertort in the 1890s (+8 =4 -0; first to eight wins) under Royal patronage. Thereafter, Britannia's genetically engineered nobility monopolized the title.
Mr. CJ: Horror. Absolute, unstinting horror.
Also mild amusement.
Incidentally, Lelouch's abnormally high IQ (220) could owe its existence to one of two scenarios. Either:
1) Britannia's massive, century-long breeding program (with mandatory testing) gave them a large enough sample size that it's plausible
2) It uses Binet's older "mental age" measurement, and was administered very early. Since the Britannian eugenics program began in the 19th century, I find this more plausible.