As the title says, don't let your heart go down.
Xuan Yue spent a thousand years of prosperity and lost the person she loved most.
Xuan Yue said to K that if your heart is hurt, it will heal in seven or eight hundred years. Therefore, I will bear all the injuries. You only need to watch from the side. You cannot be hurt. You do not have so much time to heal.
Xuan Yue is a monster shou, K is a scumbag attacker, and Yu Suze is a bombardier attacker.