Yeon-woo's twin brother disappeared five years ago, only for his pocket watch to suddenly fall into Yeon-woo's hands. Inside, Yeon-woo found a hidden diary. "By the time you hear this, I guess I will already be dead..."

Obelisk, the Tower of the Sun God, is a world where several universes and dimensions intersect. Yeon-woo's brother had died after being betrayed while he climbed the Tower, and after learning the truth, Yeon-woo decided to climb the tower with the help of his brother's diary.

"From now on, I am Cha Jeong-woo."