Before her marking ceremony, the female lead discovers Alpha Leon only pretended to love her to win the Alpha King election—so in a drunken fury, she spends a night with a stranger, then swaps grooms with her stepsister to marry the rumored "Sea Demon" Alaric, hoping to use his power to become the next female Alpha King. But the handsome stranger who took her first time turns out to be the Sea Demon himself—and a new life is already growing inside her.