They got lost together.
In the wicked forest, with the witch lying dormant and the wolf on his lunchbreak - for there were worse things than fairytales out there in the woods, and he knew for sure that he could bring them closer.
They found eachother quickly, the three looking bewildered, lost in the twilight and the brightness all around, their fumbling, pallid fingers clutching what they could. All of them screamed and cried with anguish, curled into compaction as they wailed for the loss - of what, they could not decide. They stood and looked at eachother, sensing their sentient mistake.
Xemnas was the first to cover his eyes and reach back for the door, barely realising that here in the wicked forest there was no door handle, and no hairpin for the lock - there was no lock.
And after a time, he'd even forgotten the door.
So he turned to his fellows and took their hands, strong and dominant over them all, a messiah to lead them forward through the endlessness.
They could walk forever, if he led.
I guess i should explain? This is inspired by 'Tango De Roxanne' (from Moulin Rouge - great movie, great track!), and it has nothing to do with the song but the scarily haunting beat.
Kind of an Origin fic. I believe that Xemnas did not go nobody, so to speak, alone. Three is a magic number, right? So Saix, Xemnas, and Xigbar venture forth into the darkness.