For Gu Qingcheng's death to seem believable, he had to go into hiding.
Yun Liuli knew that they wouldn't be able to see each other for a few years, and they wouldn't even be able to contact each other. Since Gu Qingcheng was going to "die", he had to be like a "dead person".
"We'll agree on this. When my hair reaches my waist… you'll come back!" Yun Liuli choked up as she looked at Gu Qingcheng. "You'll come back and marry me, and I'll provide for you!"
Gu Qingcheng nodded, replying, "Okay! I'll wait for you to provide for me…"
Yun Liuli bit her lip, and tears threatened to spill from her eyes once more.