A younger brother burdened with debt lives under the roof of his older brother's home, where he increasingly finds himself accidentally catching glimpses of his sister-in-law's underwear and cleavage. Each encounter fuels his jealousy toward his brother and intensifies his hidden desire for his sister-in-law, driving him to shout in frustration, "Damn it! Why does my brother always get to have all the fun!" His deep-seated inferiority complex becomes fixated on his sister-in-law, ultimately leading to a shocking turn of events in which she is assaulted by the younger brother and his accomplices. What begins as fleeting temptation in everyday life spirals into inevitable destruction.