military!au: Before being drafted, Dean was only weeks away from becoming a doctor. Instead he finds himself on the battlefield, killing men rather than saving them. There he gains a fearsome reputation, becoming almost legendary for his ability to walk away from brushes with death- until he’s badly injured trying to rescue his men during an ambush. After recovering, haunted by his failure to save the lives of the men he promised to protect, he finishes his training and starts patching up soldiers. Working at a small hospital, still seeing men die every day, he stumbles across a patient named Castiel, who’s not expected to live. However, he surprises everyone but Dean, who thinks he’s too stubborn to die, by soldiering on. Tending to his wounds, Dean finds himself unexpectedly charmed, and slowly their relationship deepens. Unfortunately, Castiel is soon going to be healthy enough to go back to the front lines, and Dean can’t bear to send him to his possible death.