Ama's Death (Situational Irony)
After Kyungha's quixotic and extreme journey (which took her out of her isolation and into a snowstorm), she arrives at Inseon's house only to find Ama dead. This letdown after heightened tension exemplifies situational irony.
The Narrator's Reliability (Situational Irony)
At various points in the novel, Kyungha questions who is in fact a spirit and who is alive. The fact that she considers her own reliability as a narrator demonstrates situational irony because the distinctions between apparitions, imagination, and reality cease to matter in the first place. Against most expectations, Han makes no attempt to answer Kyungha's questions or to value objective knowledge over other experiences such as memory and imagination.
