He could never forget that day.

He was young and delusional, a fool in love who didn't know how far he would be able to go for love.

The wind beat against his face as the city went up in flames after a huge explosion caused to defeat someone very dangerous. His breathing was agitated, his hands shaking into fists.

On the rooftop there was someone else, a young girl with very long hair, her back to him. Their gazes met for the first time that day, a spark taking hold of them both, a flame that had not been extinguished even over the years, not even to this day.

He was already an adult, he was 28 years old, but even at that age he could not stop the strong beating of his heart at the sight of his beloved's back uncovered. He was as nervous as the first time he had the pleasure of meeting her body at the age of 24.

She was changing on a train back to Korea, really unaware that Taekjoo had awakened from his sleep and was watching her - her partner in demissions, the man she had never put labels on despite all the times their hearts had flipped over to see each other.