What does it mean when a man talks about practicing Sunflower Collection?

It has the following two meanings:

1. Joking: It is a way of joking, a joke between friends, and a flirting between lovers.

2. Metaphor not close to women: From Mr. Jin Yong’s martial arts novel "Swordsman", the character Dongfang Bubai has practiced the Sunflower Book and turned into a person who is neither male nor female. Because the prerequisite for practicing the Sunflower Manual is that "if you want to practice this skill, you must first surrender to the palace." After a man surrenders to the palace, he loses that ability and is no longer close to women.