This catchphrase is used not only to mock a group of females that has an androgynous appearance like Li Yuchun, but as an endorsement similar to saying someone can "hang with the boys".
"Ye Men" (??) in Chinese is used in a way comparable to "bro" in the United States.
?, meaning "grandfather", can also be read as "masculine" (young males in Northeast China use the slang term ? as a personal pronoun in an impolite context).