His Promise Became My Cage

Human researcher Erin travels to Emerald Atoll to study Auren, a fearsome deep‑sea Siren. When she tries to flee, Auren captures her and forces her to take a transformative magic pearl. Trapped underwater, Erin regains lost childhood memories of their old promise. To legally stay with him, she tricks and imprisons Auren until Sirens gain sentient‑being rights. She confesses her love, they reconcile, and raise their tailed child.