There are reasons behind why the main characters in dramas are suffering from various illnesses.

In the SBS drama "That Winter, The Wind Blows", Oh Young (Song Hye Kyo) lost her sight to a condition called pigmentary degeneration of the retina when she was a high school student. Also, in the tvN drama "Nine: Time Traveling Nine Times", Park Sun Woo (Lee Jin Wook) gets diagnosed with 4th stage brain tumor and is told to have only one year left to live.

In the drama "That Winter, The Wind Blows", the cause of Oh Young's blindness is a mystery. Oh Young could have prevented losing her sight if her condition was treated early enough, right when they discovered the brain tumor. However, Secretary Wang (Bae Jong Ok) prevented Oh Young from receiving any treatment, which is the reason why Oh Young suspects Secretary Wang. Viewers are curious about the secretary who devoted 20 years of her life to serve as Oh Young's eye.

Also, Oh Young's blindness aids Oh Soo's (Jo In Sung) plans to steal her money. If Oh Young was not blind, she would have found our about her real brother's death and Oh Soo would not have been able to pretend to be her brother. However, all of this was possible because of her condition.

In the drama, "Nine: Time Traveling Nine Times", the main character Park Sun Woo is diagnosed with a type of brain tumor called, glioblastoma tumors in the 4th stage. He is told that surgery is not an option because of the location of the tumors. Park Sun Woo is told to have just one year until he has to say goodbye.

There are a lot of things Park Sun Woo wants to do before he dies. He needs to take revenge and find love. Park Sun Woo somehow gets 9 chances to travel into his past.

This drama is about time travel. By using the fragrance sticks his brother had left, Park Sun Woo travels to the past two times. During the first time of his travel, he believes he is hallucinating as a result from the shock after hearing his condition. However, he realizes his ability to time travel is not a dream when he sees the scar he received from time traveling.

In the two stories, the fatal diseases the main characters are suffering from are playing out to be crucial factors in the development of the stories. Their conditions allow the viewers to watch what Oh Young and Park Sun Woo will do at times that call for drastic measures.