What was the omen in the red room story?

In "The Red Room" by H.G. Wells, the omen is represented by the unsettling warnings of the elderly inhabitants of the house, who insist that the room is haunted. Their fearful demeanor and ominous predictions create a sense of foreboding, suggesting that the room holds a dark and dangerous secret. This atmosphere of dread foreshadows the protagonist's terrifying experience within the room, highlighting themes of fear and the unknown. Ultimately, the omen serves to build tension and anticipation as the story unfolds.