After transmigrating, Shen Yiti learns that she is a general's daughter who has lost the protection of her father and elder brother. Just as she thinks she can use her martial arts skills to roam the world, a delicate voice suddenly rings in her mind: "Who are you? Why are you inside my body?"
Ten years later, the female general known as the Rakshasa is sent to Nanling to receive an envoy from the Southern Frontier Kingdom. There, she inexplicably gets caught up in a series of murders. While investigating the case, she meets a red-clad young swordsman who roams the world. He is breathtakingly handsome, but not especially bright. The first time they meet, he says, "Heaven sent me to save you."
From then on, he stays by her side, escorting the envoy from the Southern Frontier Kingdom back home. They face one difficulty after another, but stand together and make it back to the imperial capital, falling in love along the way.
But while carrying out her orders, she never expects to dig herself into such a deep hole. In the palace, the Rakshasa stares at the marriage contract in her hand, unable to believe it, and asks the emperor to repeat himself.
"I will let you investigate what happened back then, but you must accept the marriage to the envoy from the Southern Frontier Kingdom."
"That old bastard dares to covet me? Has he even thought about whether he's worthy? He's one foot in the grave already!" She can barely contain her urge to cut someone down.
But the emperor's decree cannot be disobeyed.
"Fine. Then tell him for me: I hope I'm in a good mood, or I'll use him for sword practice at any time!"
"You... You came to steal me away?" His long black hair falls loose down his back, his clothes are bright red, and his dark, deep eyes look just like they did when they first met.
"I told you, I came to save you. I know you don't want to marry him."