She is just waiting. After these nine lifetimes of love are over, she can then stay with him forever.
Although he has entered reincarnation, she still cares about him and sneaks into the mortal world secretly, just to stay with him and spend nine lifetimes together. I just don't know if, after nine lifetimes, he has seen through the world of mortals and can no longer remember a person like her. ． ． ． ． ．