Minerva is the first sister to react to Trujillo's regime, causing the rest of her family to have to make a decision whether to get involved. She's rebellious, self-confident, and outspoken, qualities that make her a natural leader in the movement against Trujillo and later lead to her title of "La Mariposa", the brains behind the revolution. Her discovery of her father's second family and his deceit in hiding Virgilio's letters to her angers her to the point that she knows she must now decide what values and ideals will be the focus of her adult life. Minerva says that "something has started which none of us can stop," and committs herself to the revolution and stopping Trujillo's reign of terror. She shows herself to be a worthy opponent of Trujillo when she slaps him for his sexual advances. She shows no fear of him even when he deprives her of her physical and mental freedom.

Minerva is a person of courage who stands up for what she believes in, knowing it will cost her and her family dearly. In the end, she learns to appreciate her family and their points of view. She dies returning from a visit to her husband in prison.