Lim Hyuk-ju lives in a tiny apartment in a bustling student neighborhood of South Korea's capital, Seoul.
The apartment is just 30 sq. ft. — basically a walk-in closet with a toilet, shower and shared kitchen — for $400 a month.
"It's uncomfortable, because when I lay down my legs hit the back wall," explains Lim, 25.
She has to be quiet because the walls are thin. Lim's neighbors are all young people like her, studying 15 hours a day for job entrance exams.