Attack on Titan (Japanese: 進撃の巨人) is a Japanese manga series both written and illustrated by Hajime Isayama.
It is set in a fantasy world where humanity lives within territories surrounded by three enormous walls that protect them from gigantic man-eating humanoids referred to as Titans.
Story: A century ago, the grotesque giants known as Titans appeared and consumed all but a few thousand humans. The survivors took refuge behind giant walls. Today, the threat of the Titans is a distant memory, and a boy named Eren yearns to explore the world beyond Wall Maria. But what began as a childish dream will become an all-too-real nightmare when the Titans return and humanity is once again on the brink of extinction ?
Biography of the author: Hajime Isayama (諫山 創 Isayama Hajime, born August 29, 1986) is a Japanese manga artist. His first and currently ongoing series is "Attack on Titan." This is experiencing success with 52.5 million copies in circulation as of July 2015.