Character Arc
Lee Jae-yoon is one of the two leads of Newtopia, a young man recently back from his time as a soldier whose relationship with Kang Young-joo has cooled to the edge of a breakup. When a sudden outbreak throws Seoul into disarray and separates the couple across the city, the romance he was ready to walk away from becomes his reason to keep moving. His military training gives him the resourcefulness to navigate a collapsing city, while his unresolved feelings give him the motivation.
Across the season, Jae-yoon's arc is essentially a long, obstacle-strewn journey to reach Young-joo's apartment building, where she is trapped. The series mines both tension and comedy from his single-minded determination, pairing genuine danger with the awkward, very human business of trying to reconcile with someone you were about to leave. The surrounding threat is handled in general, non-graphic terms, keeping the focus on his persistence and the relationship at the story's core.
By turns earnest, exhausted, and quietly funny, Jae-yoon embodies the show's central idea that an apocalypse can clarify what matters. His growth is measured less in combat than in what he is willing to risk to get back to Young-joo, making him the emotional engine of a story that frames survival as an act of love. This characterization is AI-authored and flagged for fact-check.