S1·E21 Sacrifice

When Song Xuanren and Song Xuanying are fighting against each other, Fengjiu recognizes the Demon Knife. She fights back the attack for Xuanren, and warns Xuanren and Ye Qingti to not be hurt by this knife. At the end, Qingti stands up to fight back alone, letting Fengjiu and Xuanren escape. After this, Xuanren is sure that Fengjiu is indeed fond of himself. Therefore he decides to forget all that has happened and start over again with her. On the other hand, Nie Chuyin realizes Xuanren is in fact Emperor Dong Hua and holds back due to fear. Fengjiu wakes up after the faint and has a hard time knowing Qingti lost his life for saving her. She decides to mourn for him for three years. She leaves the Palace, and jumps off a cliff in front of Xuanren. Since then, Xuanren becomes heavily ill, and dies in depression. When Dong Hua wakes up, he has forgotten all the things he experienced in the mortal realm.