Born under the tree with the spiritual roots of heaven and earth, "live and die", Shen Chaohua's fate is to live and die, and live no longer than one day. The only reason for her existence is to be the perfect elixir to nourish her sister. However, in the last moment of her life, she was unwilling to marry someone else, and resolutely sacrificed her body to summon the legendary demon king, Xie Changye, who had been suppressed for thousands of years.
She sacrificed her freedom in exchange for him changing her fate against fate. From then on, the world lost a meek medicine man, and gained a "Mayfly Sword Master" who took the name of the sword and was born to face death.
He is the feared Eternal Demon Lord who regards all people as ants, but he is bound by a mortal who lives and dies. He taught her how to kill and taught her magic skills. He wanted to watch an interesting drama of ants struggling, but unknowingly, all his eyes fell on her.
When the snare of fate tightened again, when the betrayal of family affection and the pursuit of the three realms followed one after another, she burned all her beauty, just for a moment of brilliance. He stepped on the void just to protect her for the rest of her life.
This is an entanglement that begins with a transaction, a choice about life, morality and love. When the mayfly tries to shake the sky, when the demon king is willing to fall into the world of mortals, will their fate end together in eternity, or in nothingness?
