It was hard to see that it was her arm.You see, what has happened is that the woman's cup has lined up with the upper part of her arm. The way that her hair is laying about her arm creates an illusion that it is a rigid phallus that is in the cup. I could see where someone might be confused at first viewing of the photograph, but upon further inspection, and based on common sense and social mores, you would see that it is fact not a phallus at all.
Glad I could help.