Character Relationship Map: No Breathing

Characters

• Jo Won-il (played by Seo In-guk) — protagonist

  A once-promising swimmer who abandons the sport after a devastating family tragedy, Won-il begins living recklessly and faces expulsion from school. Jae-seok brings him to a physical education high sc...

• Jung Woo-sang (played by Lee Jong-suk) — protagonist

  A nationally recognized swimmer who reaches first place after Won-il leaves the sport, Woo-sang is disqualified from national tryouts after getting into trouble and must rebuild his career. He resents...

• Jung-eun (played by Kwon Yu-ri) — supporting

  Jae-seok's daughter and a young woman connected to both central swimmers, Jung-eun captures the hearts of Won-il and Woo-sang. Her presence intensifies their rivalry beyond the pool, while their share...

• Woo-sang's Mother (played by Kim Young-sun) — minor
• Woo-sang's Father (played by Sunwoo Jae-duk) — supporting

Canonical Relationships

Family, romantic, and professional connections based on plot evidence.

• Woo-sang's Mother → Jung Woo-sang (mother)
• Woo-sang's Father → Jung Woo-sang (father)
• Jung-eun → Jung Woo-sang (Romantic Crush) — Romantic interest that intensifies the competitive dynamic between the two swimmers.
• Jung-eun → Jo Won-il (Romantic Crush) — Romantic interest that provides Won-il with a reason to reconnect with swimming and life.

Story Dynamics

Alliances, conflicts, and narrative interactions that evolve throughout the story.

• Jo Won-il → Jung Woo-sang (Conflict Rival) — Former swimming rival whose competitive nature clashes with Won-il's apathetic attitude.

Story Analysis

Two young swimmers confront loss, rivalry, affection, friendship, and maturity through a demanding return to competition.

Plot Progression

1. A Champion Lost — A promising swimmer loses his father during a competition and then loses his mother. He abandons swimming and begins living recklessly.
2. The Forced Restart — An expulsion threat leads a family friend to send the protagonist to a physical education high school. The move creates an opportunity to return to swimming.
3. Rivalry Under Pressure — A former rival, once overshadowed, has become a national swimming star. Disqualification forces him to rebuild his career while resisting the protagonist's return.
4. Love And Training — Jung-eun captures the hearts of both young men and intensifies their rivalry. They train for a major competition while struggling with friendship and affection.
5. The Swimmers Mature — The upcoming competition becomes a test of athletic ambition and personal growth. The rivalry serves as a rite of passage into maturity.