In Myeongdong, go to Daiso Myeongdong Main (43 Myeongdong-gil) or Myeongdong Station (134-1 Toegye-ro), 10am–10pm. It's a popular line, so if your type is gone, try the other store. The EGF Wrapping Steam Mask is ₩2,000 a sheet with 11K orders, a nice treat on a trip.