One day, Yen Hong, a middle-aged Go player who's lived life listlessly, suddenly died of a heart attack.
Transformed into a spirit, he meets an outspoken angel, Saoirse, whose assignment was to extradite him to heaven. However, though Ian has no more time on this earth, he was unable to rise up to heaven...
Saoirse had no recourse but to turn to the angel chief, who explained that Ian had yet to fulfill a special promise made in his past. Before he is allowed into heaven, he would have to seek out the person with whom he made the promise – a girl from his junior high Go club, Shannon.
The angel assigned to extradite our protagonist. Although of angelic essence, she is extremely impatient, outspoken, and biased against humans. Her biggest wish is to quit her job.
The male protagonist. Competitive and impulsive, he is a Go teacher in his forties... After he died suddenly of a heart attack, he was shut out of heaven due to an unfulfilled promise from his past. To remedy this, he needs to travel with Saoirse the Angel to an alternative dimension to find someone from his junior high years.
The female protagonist. She was a year above Ian in junior high school and a member of the Go club. She has long red hair, inherited from her mother, and comes across as cold, distant, and aloof. She beat the then-undefeated Ian in their first Go match, leading to a secret pact between the two.