Bahamut. There's no such thing as eternity.
It was true. One thousand years dreaming the same dream, over and over again, seamlessly overlapping an ending over a beginning over an ending until it was one perfect circle. No one could tell when the previous cycle ended and when the new one begin, and after a while, it didn't matter anymore. It was clockwork---predictable, precise, reliable. Yet this time, he had allowed the breach, permitting this Zanarkand to meld with the other, tearing the thin fabric between the worlds (which one was real? this one? the other? it made little difference to him) and soon the dream would end.
There were times when he found himself confused. Zanarkand existed because of their dreams. They existed because of Yu Yevon. Yet Yu Yevon was the summoner of Sin, and Sin was the destroyer of Spira. Sin was the reason why the dream continued, and if they wanted the memory of Zanarkand to continue, they had to go on dreaming. After a while he couldn't remember which was the cause and which was the effect, and he couldn't tell whether he was a boy or a dragon or an aeon anymore, and he couldn't remember how it was to be really alive. He could never untangle himself from the confusion, from the never-ending spiral of destruction and death, so he would end up going to the blitzball stadium to watch the Abes play instead.
Perhaps that was why he had allowed the lapse in the cycle. That was why he had allowed a dream to become almost-real, to wander in the land of the living.
One thousand years was a very long time. It felt even longer when nothing changed, nothing evolved, nothing happened. It was an eternity. But then again, there was no such thing as eternity if it ended, was there? He smiled to himself, watching the dream-sea and the dream-sky, and the dream-people going about their daily lives. Memories preserved for a millennia, yet no one really remembered any of them.
He was tired of dreaming. He was waiting for the final call of his summoner, waiting for the dream to end.