KARA's Gyuri spoke up on her group's somewhat surprising and unexpected Japanese advancement.

Appearing as a guest on MBC's 'Quiz to Change the World', she recounted the moment when she knew that KARA would be a huge hit in Japan.

"I didn't know that we would be promoting in Japan," she said. "Our CEO said we should have a performance in Japan, so we went without any pressure. We had a good response, so we hurriedly debuted in Japan."

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"We planned a one-hour concert in Shibuya," she continued. "However, so many people showed up that we had to cancel after 15 minutes." This incident spurred on KARA's Japanese plans, she said.

Since the Japanese promotions had practically come out of nowhere, the girls had little time to prepare, Gyuri recalled, even having to jot down bits of Japanese on their hands!