She was not dumb.
As a genius of Fox Immortal Island, she was even considered absolutely intelligent. This mysterious Daoist Feng had saved her life and fended off a Fox Immortal Island expert. He had even mentioned a huge problem that was stirring in Fox Immortal Island! All of this was to help her, as well as Fox Immortal Island.
"Why am I helping you?" Qin Yun drank the wine and glanced at Qing Shuang. He said with a laugh, "Would you believe me that because of your impressive talent and your cultivation of sword arts which happen to use the same Yin Yang Dao as mine, I suddenly have the intention of taking you in as a disciple?"
Qing Shuang immediately showed a look of delight when she heard him. She plopped to her knees and said, "Greetings Master!"
The demons were more direct than humans.
With someone so powerful before her, she obviously had to cozy up to him!