Jeannette, some Jewish thinkers and rabbis say that Cain was a product of Eve and Serpent, which is reason why Eve is called mother of all living, while this is not mentioned about Adam. When Eve had bear a child with Serpent she said "At his birth, the exclamation was wrung from Eve, 'I have gotten a man, through an angel of the Lord". Other texts say something similar: "And Adam knew his wife, who had desired the Angel; and she conceived, and bare Cain; and she said, I have acquired a man, the Angel of the Lord." and "And Adam was aware that Eve his wife had conceived from Sammael the angel, and she became pregnant and bare Cain, and he was like those on high, not like those below; and she said, 'I have acquired a man, the angel of the Lord [the serpent of the Lord]." The fallout of Adam and Eve was not eating forbidden fruit, but having unatural relationship with Serpent. God gave Adam an opportunity to admit the crime, but he refuses and blames Eve. Reading various materials I have not seen any specific meaning to the fig leaves except to the references where all flora refused to hide Adam and Eve, and only fig tree felt pitty and hid them from the wrath of God.
Also Talmud mentions that Eve picked the forbidden fruit and fed it to the animals as well, therefore, all living was corrupted, not only mankind. Genesis without deep explanation is incomplete that it does not make much sense.