Sei's ex-boyfriend of five years. A man who loved through actions rather than words and was a 'home' and 'nest' to her. Despite his meticulous care for Sei within their familiar routine, he ultimately chose another woman, leaving the deepest scars on the person who felt safest with him.

A woman who is divorced and raising a child. She met Han Jaehyun through a dating app and became close to him. The fact that Jaehyun had a long-term lover named Sei and the history between those two become the center of conflict in the story.

Sei's current boyfriend. He is younger than Han Jaehyun but older than Sei. A man who is kind and meticulous but firm when necessary. He doesn't try to force Sei's past and scars away; instead, he accepts even her anxieties without finding them burdensome. Rather than confirming his love with words, he shows it through consistent actions, ensuring Sei never feels alone in their love again.