Even Rome fell (—and you weren't much of an Empire at all)

When Icarus flew too close to the sun, the gods burnt his wings and let him fall to his death. When the worlds need seven sacrifices to keep turning, Kawahira curses the seven monsters who'd burn it all to the ground on a whim. In at least eight different parallel worlds, Byakuran learns this knowledge the hard way. [Cross-posted on ao3. Tags inside.]