Telephone Booth of Unspoken Words

What if you found a phone booth from which you could call a loved one who is no longer there? What if, after a few rings, you heard your dear one's voice — and you would hear what they wanted... to say but never had the chance to?
 
Every evening, little Kan Chian met her dad by the phone booth on an ordinary street in Seoul. When her father passed away, the girl desperately wished to talk to him again… and discovered that if you truly want it, you can hear the last thoughts of those who have departed from the receiver of that very booth.
 
Now Kan Chian has grown up — and has founded a center for psychological help for those who have lost loved ones. Before you are five stories of her clients who have undergone a difficult path of accepting loss… and the story of Kan Chian herself, who is yet to understand why the phone booth revealed its secret to her.