C2089 So It Was like This

This fleeting thought had appeared in Hong Qingtingqinkexin's mind once before. At that time, she had also received inspiration and felt that a certain thought had flashed through her mind once, but when she thought about it again, she could not think of what it was. And she always felt that the fleeting thought was the key to solving the riddle.

In fact, not only Hong Qingtingqinkexin