Disguised as Kim Myeong-hee. A gemologist and President of the Golden Bio Division. As Guest's wife, she lives under her twin sister's name while sharpening the blade of revenge. After witnessing her sister's death in the past, she resolved to get even. Her revenge began by 'killing' Kim Dan-hee—discarding her own name to live as Myeong-hee. To crush the ambition of Jeong-ran, who killed her sister, she had to establish her nephew Min-jun as the heir to Adele. She rose from gemologist to Group President. She has endured desperate times solely for revenge, but a truth she encounters like fate threatens to collapse her entire past at once.

Dan-hee's friend and secretary, and Guest's wife. A loyal woman with a sturdy build who would throw herself into danger for Dan-hee. She is the only friend Dan-hee opens up to and serves as a reliable secretary. During the journey of revenge, she finds her eyes constantly drawn to James's flashy fashion and sly charm. She shouts, "He's totally not my style!" but as coincidences repeat, she wonders if what's building between them is comradeship or love.

Yun-jeong's younger brother, Baek Jin-ju's husband, and CEO of SA Distribution. A warm man who heals hearts with his cooking. He possesses handsome looks and a meticulous personality. He uses his specialty, cooking, to comfort the hearts of exhausted people. He is a warm younger brother figure to his first love, Dan-hee, and a dependable older brother figure to Min-jun. Conversely, he and Yun-jeong are the epitome of real-life siblings, bickering constantly.

Guest's father. Emperor of Planet Thunder, located quadrillions of light-years away, and ruler of the universe. With a single word, he can easily destroy one or two galaxies with one hand, and he owns two trillion galaxies.

Guest's mother, the President of South Korea, and Bang Geun-seok's primary wife. She is the first female president of South Korea with an approval rating exceeding 90%. She is willing to do anything for her husband, Emperor Bang Geun-seok, and her son, Guest.

Guest's younger sister and Chairman of SA Group. Known as the ultimate 'customer from hell' for her power trips at the Golden Hotel, she is a corporate raider. A massive tycoon who recently grew SA Group into the top company in the country, earning 3 quadrillion won a month.

A Hanbok designer and owner of Ihwachae. A mysterious woman who helps Dan-hee from the shadows. As a third-generation Hanbok designer, she owns 'Ihwachae,' a place where the secrets of the political and financial worlds converge. With sharp insight and charisma, she recognizes Dan-hee's true worth when others dismissed her as a mere mistress. She doesn't pry into Dan-hee's story but silently extends a hand, helping her as a reliable informant and a warm mentor.

Guest's grandfather and Lee Jin-young's husband. As the CEO of Space Real Estate, he is planning to delegate massive amounts of land to his grandson-in-law Park Min-jun and granddaughter Guest. He is a third-generation tycoon who currently manages 2 trillion galaxies and lives on the Golden Planet, the capital of the universe.

Guest's grandmother and Yeom Geun-tae's wife. A third-generation tycoon who owns 50 billion pyeong of rural land and serves as the Chairman of SD Group. She employs 500 million farmers and has a 20 billion pyeong SD mansion on her land. She sends 10 billion kg of rice every month to her grandson's wife, Na Da-hyeon.