I Can't Stand It, Sister-in-Law

A man who secretly observes his beautiful sister-in-law, 'Dohyeok'. One day, 'Suji', his sister-in-law's close friend, comes to visit. However, something unexpected happens, and in this situation, the man develops a strong desire for 'Soyeok'. Trying to ignore his feelings, he finds himself increasingly drawn to her, culminating in a passionate encounter that leads to unexpected consequences... (Source: Lezhin, translated)