Summary for those who may struggle with English:
Heeryang was a soldier in the military and was stationed at one of the deadliest regions of the country. He became very jaded about his life after his team was ambushed and almost completely wiped out. The surviving soldiers said everyone would have died if Heeryang had not come back to help them fight. They pleaded with the higher ups in the military to forgive Heeryang for disobeying orders, as it resulted in him saving their lives.
The higher ups still wanted to punish Heeryang. He was awaiting his fate when he was visited by the king's younger brother, who offered Heeryang the position of military commander in his area. The king's younger brother persuaded him by saying he should seize the opportunity to make his life better and elevate himself in society, as it would be a slap in the face to the family who threw him away (Heeryang's father). Heeryang accepted the position and worked very hard to defend the border, which earned him a reputation of a fearsome and competent leader. He swore to repay the king's younger brother someday.
Fast forward a few years later, Heeryang is a military noble and the country is on the verge of war. A handful of council members are against going to war, but the king's younger brother wants to go war anyway. He and Heeryang discuss the situation in private and reach the conclusion that the council members preventing the war must die. He then tells Heeryang it is time to repay his debt, which implies that he wants Heeryang to help him kill the council members.
Hopes this helps!
Heeryang was a soldier in the military and was stationed at one of the deadliest regions of the country. He became very jaded about his life after his team was ambushed and almost completely wiped out. The surviving soldiers said everyone would have died if Heeryang had not come back to help them fight. They pleaded with the higher ups in the military to forgive Heeryang for disobeying orders, as it resulted in him saving their lives.
The higher ups still wanted to punish Heeryang. He was awaiting his fate when he was visited by the king's younger brother, who offered Heeryang the position of military commander in his area. The king's younger brother persuaded him by saying he should seize the opportunity to make his life better and elevate himself in society, as it would be a slap in the face to the family who threw him away (Heeryang's father). Heeryang accepted the position and worked very hard to defend the border, which earned him a reputation of a fearsome and competent leader. He swore to repay the king's younger brother someday.
Fast forward a few years later, Heeryang is a military noble and the country is on the verge of war. A handful of council members are against going to war, but the king's younger brother wants to go war anyway. He and Heeryang discuss the situation in private and reach the conclusion that the council members preventing the war must die. He then tells Heeryang it is time to repay his debt, which implies that he wants Heeryang to help him kill the council members.
Hopes this helps!

