Overview
Young-ho doesn't have any dreams for his life. He has been studying for three years to enter a university. He decides to send a letter to his childhood friend So-yeon. But her younger sister So-hee receives the letter instead of her sick sister. So-hee writes back to Young-ho, pretending to be So-yeon. Meanwhile, So-hee takes care of her sick sister and also runs a secondhand bookstore with her mother.
| Actor | Age then | Age now | |
|---|---|---|---|
 | 31 | 35 | |
 | 34 | 38 | |
 | 31 | 35 | |
 | 28 | 32 | |
 | 38 | 43 | |
 | 51 | 55 | |
 | 56 | 60 | |
 | 22 | 27 | |
 | 40 | 45 | |
 | 32 | 36 |