A trace of a woman's soul is attached to an ancient sword, looking for her reincarnated sweetheart. Although the other person has brought memories of the past life, those memories are vague to him, like a dream.
In order to stay in the world, a woman recognized a young man as her brother and sister, and temporarily parasitized him, looking for a strange flower called Qiye Lingxi, which is said to have the effect of awakening sleeping memories.
She gradually discovered that the boy's Dantian was the best greenhouse for cultivating Qiye Lingxi.
The sweetheart finally remembered that past incident.
The seven-night connection connects nearly eight hundred years of time, intertwining the fates of the three people...