Attack on Titan is a Japanese manga series written and illustrated by Hajime Isayama.
The story revolves around a boy named Eren Yeager, who lives in the town of Shiganshina, located on the edge of Wall Maria, the outermost of three circular walls protecting humanity from Titans. In the year 845, the wall is breached by two new types of Titans, named the Colossal Titan (alternatively named the Colossus) and the Armored Titan. During the incident, Eren's mother is eaten by a Titan while Eren escapes. He swears revenge on all Titans and enlists in the military along with his childhood friends, Mikasa Ackerman and Armin Arlert.