Hajime Isayama, creator of Attack on Titan, talks about how he came up with the idea for the blockbuster manga in a video interview with BBC News -- and he reveals he was rejected by so many publishers that when an editor did show interest, he wondered, "What's wrong with this guy?"

"I was beginning to give up," recalls the 29-year-old artist, "because there are so many people who want to become manga artists. I didn't think I could become one of the big ones. [...] If I didn't become a manga artist, maybe I'd have tried to work at an Internet cafe."

Isayama also talks about a video game that first gave him the idea for a manga about monsters. "I thought it would be interesting if those monsters ate humans," Isayama says. The story also reflects his experiences growing up in a rural area. "As a child, I remember thinking, 'All living creatures must get nutrition from other living creatures to survive,'" he says. "We might call it cruel, but it is actually the norm."

Attack on Titan has become one of the bestselling manga of all time, with more than 52 million volumes in print worldwide.