This is a Guilty Crown question. For those you who do not know Guilty Crown, check out Kuro's statement on the wiki page:
After the spread of the "Apocalypse Virus" in Japan in the year 2029, the country has been placed in an emergency state. Since the spread of the virus, the Japanese government lost all of its foundations, and the reign of the international organization known as GHQ began ruling the country. Now Japan is in a state of martial law, which is enforced by the GHQ, and is considered a "quasi-independent" nation.
10 years pass, and we see the story through the eyes of Shu Ouma, an average 17-year-old teenager who lives a normal life. However, his normal life style is soon shattered after his chance encounter with Inori Yuzuriha, who eventually involves him with the anti-government group she is a part of, known as Funeral Parlor, or Undertaker.
What is a Void?
A Void is an object that is determined by the person's heart and genes (specifically introns). For Guilty Crown, Shu has the King's Power to pull out Voids and use them as weapons. Just like fingerprints, each person has a unique void.
Pretend you are a character in Guilty Crown and Shu is about to pull out your Void. What would be your Void? If you are a guy and prefer a woman to pull out a Void out of your chest. Just imagine Inori doing it to you.
For the ladies: