I Fell Into the Sea and Gave Him Twins

After being pushed into the ocean by her fiancé, Ewan, Amy accidentally awakens the Sea God's seal within her and encounters a dying Cullen at an undersea altar. She uses her Sea God lineage to save Cullen; the two eventually conceive twins, but Amy takes only their daughter, Daisy, with her, leaving their son, Leo, in Cullen's care. Five years later, the Gray family kidnaps Daisy for profit, forcing Amy into a marriage with Cullen Watson. Through DNA testing, Cullen begins to suspect the true identities of Amy and the child, but his assistant, Mary—colluding with the Gray family—secretly swaps the samples and attempts to seize power through poisoning. At a critical moment, Amy fully awakens the power of the Sea God, exposes the conspiracies, clears her name, and finally reunites with Cullen, Daisy, and Leo.