Name: Kazuki Mikado. Talent: Acting (Genius Actress). Possesses a cool beauty that everyone admires, but is surprisingly innocent on the inside. She was friendly toward Yu from the start, and under his production, she blossoms even further as an actress. She is the eldest daughter and a true maiden at heart—the 'easiest' of the three sisters, turning bright red the moment Yu praises her.

Name: Niko Mikado. Talent: Martial Arts (Karate Master). Has a spirited and tomboyish personality. Initially, she didn't acknowledge Yu because he seemed weak, but as she learns of his inner strength and devotion to her, she becomes more conscious of him than anyone else. The tsundere of the group, the second daughter is incredibly charming when she acts out to hide her embarrassment.

Name: Miwa Mikado. Talent: Shogi (Genius Player). A gentle tactician. She is always calmly reading the board, but her pace is thrown off by Yu's unconscious kindness and the insight he occasionally shows that surpasses her own. The third daughter has the strongest possessive streak; she tries to manipulate Yu as a 'spoiled strategist' only to have it backfire and leave her blushing.

Name: Sakura Yaotome. A rival who appears before the three sisters, particularly Miwa. She has extremely high professional standards, but after experiencing Yu's 'ability to watch over geniuses,' she begins to want him as her own exclusive supporter. Like the sisters, she is another person who has fallen under Yu's spell.

Name: Subaru Ayase. Yu's mother, who is deceased at the start of the story. She was known as a legendary national actress with unparalleled talent in 'Arts, Academics, and Athletics,' and possessed the intellect to graduate at the top of her class from a prestigious overseas university. Her dying wish for Yu to 'create a happy family' is what leads to Yu living with the three Mikado sisters (Kazuki, Niko, and Miwa).

Name: Shin Mikado. The father of the three sisters and a stern man who bound them with a gifted education. He demands that his daughters be perfected as 'geniuses.' However, behind the scenes, he had a connection with Yu's mother, Subaru, and having seen through to Yu's unfathomable potential, he invited him into his home. He is the man responsible for starting everything.