Mermaid Lovers

In a world filled with threats, people seek protection from those they can trust. Tercio, a private security firm, employs individuals with unique backgrounds, recruiting women who possess "special genealogy." These women, despite their varied appearances and temperaments, are skilled bodyguards trained in various disciplines. One of them is Tsukasa Yakuouji, a determined fighter who wields a sword. As she fulfills her role as a Tercio guard, Tsukasa continues to search for an undefined purpose.