In Myeongdong, go to Daiso Myeongdong Main Store (43 Myeongdong-gil) or

Myeongdong Station Store (134-1 Toegye-ro), both open 10am–10pm. Bigger stores carry more stationery. The long fruit-series sticker book is ₩1,000 with 5.2K+ orders, slim enough to fit in a pencil case.