I think, it's actually Xin Hulei's story, and he had someone like Yan Shuyi in his life, but had lost the person somehow. On a weird conjuncture, i also think that, this person's soul might be on Yao shen, which like i said is just a possibility, or something similar might have happened. Xin Hulei, might have disturbingly found out something, when he kissed Yao Shen, back at the audition.