The Parks, at one point, mention a certain foul scent Ki-Taek carries, unaware of his sensitivity to it as a reminder of his poverty, eventually driving him to murder Park Dong-Ik (Lee Sun-Kyun) and realize that he is this family’s “pest.”
The stink bug’s brief appearance in Parasite’s opening scene seems like a throwaway expository detail but is actually some brilliant foreshadowing and lends to the film’s unique use of smell as a symbolic tool for class distinction.
Kim Ki-Taek (Song Kang-Ho) hates stink bugs enough to endure hazardous gases in his home to achieve free pest treatment, yet he relates to the pesky insect more than he knows.