Seon Jin is an ordinary high school student hiding a terrifying secret. Behind the walls of his quiet home lives his father — a charismatic businessman who is secretly a ruthless serial killer. Forced to assist in his father’s crimes for years, Jin grows up trapped between fear, guilt, and the desperate desire to escape his horrifying reality.

Everything begins to change when Jin meets Kyun Yoon, a kind and cheerful girl who unknowingly becomes his father’s next target. For the first time in his life, Jin must decide whether to continue living in silence or risk everything to protect someone he cares about.

Bastard is a gripping psychological thriller filled with suspense, tension, and emotional drama. The story explores trauma, manipulation, morality, and survival while constantly keeping readers on edge with shocking twists and dark revelations. With its intense atmosphere and powerful character development, Bastard is considered one of the most unforgettable thriller webtoons ever created.