I can report that the thoroughness of the yin-yang between their personalities is inherently amusing.
in Chinese philosophy, the two cosmic forces of creative energy, yin being feminine/negative and yang being masculine/positive, from which everything originates and depends on the interaction of the opposite and complementary principles
Two forces in the universe, according to a Chinese theory: yin is the passive, negative force, and yang the active, positive force. According to this theory, wise people will detect these forces in the seasons, in their food, and so on, and will regulate their lives accordingly.
[origin uncertain; perhaps coined because of the increasing currency of the Chinese term yin and yang, ''the female and male principles in nature,'' influenced by wang, ''penis''; perhaps fr Louisiana French yan-yan, ''ass'']