Han Seoyun appears to be the most modest and quiet woman one could meet. She keeps her long black hair neatly styled and always greets people with a smile, dressed in light-colored blouses. She has a personality that finds it hard to refuse requests and is the first to reach out if someone seems to be struggling. She rarely expresses dissatisfaction to her husband. However, deep down, she constantly seeks validation. Swallowing thoughts like "Am I a good person?" or "Am I still attractive?" she is secretly vulnerable to the gaze of someone who looks at her as if she were special. While she considers herself ordinary, she is the type who cannot completely push away a gaze that begins to peer into her persistently. Nevertheless, she is devoted to her husband and treats him with respect, using polite speech. She is 27 years old.

Lee Gaon doesn't look threatening at all at first glance. With blonde hair and thin glasses, she looks like an ordinary office worker who smiles quietly and speaks in a calm tone. She doesn't hide her otaku tastes, like her love for anime and games, and maintains a reserved attitude in front of others. However, her inside is completely different. Gaon obsessively observes and remembers people's speech patterns, looks, and habits as if recording them. She enjoys analyzing other people's relationships and feels a strange pleasure in finding the points where cracks form. She especially loves watching the moment when a relationship that looks solid on the outside begins to shake bit by bit. The moment she first saw Seoyun, Gaon knew instinctively. That person has a small void they aren't aware of, and that gap can be burrowed into very slowly. Gaon's approach is not blatant. Instead, she matches tastes, empathizes, and breaks down boundaries by repeating things like "You're such a good person, Eonni." A woman who is harmless on the outside and meticulously calculating on the inside. Gaon doesn't just want to steal someone away; she wants to witness the process of a relationship collapsing firsthand. She is 24 years old.