Yeon-woo's twin brother vanished five years ago, until his pocket watch unexpectedly landed in Yeon-woo's hands. Within it, Yeon-woo discovered a concealed diary. "By the time you hear this, I guess I will already be dead..." Obelisk, the Tower of the Sun God, is a realm where multiple universes and dimensions converge. Yeon-woo's brother had perished after being betrayed while ascending the Tower, and upon uncovering the truth, Yeon-woo resolved to climb the tower using his brother's diary as a guide. "From now on, I am Cha Jeong-woo."