IU: 21 Under 21 (2012)

IU: 21 Under 21 (2012)

No. 15: IU

Birthdate: May 16, 1993 (age 19)

Why She's Hot: Most South Koreans would be hesitant to label IU as "hot" -- after all, she's affectionately known as the nation's "little sister." But this past year, IU's unique charm and undeniable hits have made her into a bona fide superstar. Her reign began with the release of her comeback single "You and I," the No. 1 song of Billboard's K-Pop Hot 100 chart of the past year. While IU hasn't hit the same level of global viral awareness as Psy, her popularity has led to success in Japan, where she celebrated Hot 100 hits with Japanese versions of "You and I" and her single "Good Day." Meanwhile, the singer remains a formidable K-Pop force in with chart toppers like "Every End of the Day" (which held a four-week run at no. 1 on the K-Pop Hot 100), "Peach," and a collaboration with her labelmates FIESTAR on "Sea of Moonlight."

Video Below: IU's "You & I"

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