In the supreme empire that ruled the entire universe, swords were the empire's strongest military force, and every sword had its own wing, born to accompany it.
Wings are highly spiritualized beings with perfect appearances. They must spend their entire lives depending on a sword to survive.
They serve and protect the swords.
The apocalypse came, and even the mightiest empire could not escape destruction.
When Gray opened his eyes again, he had returned to the day he made his pact.
That was the day he became his mortal enemy's companion and the other's wing. It was also the day he plunged a dagger without hesitation into the heart of the man who had become his sword...
If fate decrees that only one person can prevent the world's destruction, can he, given another chance, put aside his pride and become that person's possession, their protective wing, even if that person is his sworn enemy?
Or will he instead take control of the strongest sword in the universe?
