This is a story of fall and ascension. Everything has many sides, one is bright and the other is dark. Only through comparison can we discover the so-called good and bad, beauty and ugliness, degradation and sublimation in this world. This is the theory of relativity in the world. Both sides are indispensable and dependent on each other, but they are like two rays running in opposite directions, never intersecting forever. When two souls floating between degradation and sublimation intersect and put aside the theory of relativity, can they have eternity?