Five years after his twin brother vanished, Yeon-woo receives back a pocket watch containing his brother's hidden diary and learns he died climbing Obelisk, the Tower of the Sun God, where many universes and dimensions intersect. Taking up the watch and his brother's identity, Yeon-woo enters the tower himself, determined to climb it and find out who was responsible for the betrayal that killed him. This novel is the source material for the Second Life Ranker manhwa.