"Attack on Titan," the action-fantasy manga that's spawned its own multimedia empire, now has more than 63 million copies in print.

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The announcement was made in the April issue of Kodansha's Bessatsu Shōnen Magazine, which went on sale Wednesday in Japan. That figure is up from the 60 million copies revealed in September.

Debuting in 2009, Hajime Isayama’s popular series depicts the battle between the last remnants of humanity who live in cities surrounded by enormous walls and the flesh-eating giants who roam the outside world. The series initially centers on Eren Yeager, his adopted sister Mikasa Ackerman and their childhood friend Armin Arlert, who join the military after the town is invaded by Titans and Eren’s mother is eaten. The story later shifts to focus on other characters as the truth about the Titans is revealed.

"Attack on Titan" has inspired a hit anime series, which returns in April for its second season, a pair of live-action films, video and real-life escape games, spinoff manga and anime, novels, theme park attractions, and an avalanche of merchandise. There's even a line of wine from Isayama's hometown.

Kodansha published the manga's 21st volume in December in Japan; it will be released in April in North America.

(via Anime News Network)