María del Carmen Mondragón Valseca (July 8, 1893 – January 23, 1978), also known as Nahui Olin, was a Mexican painter, poet, and artist's model.

[1] The professional activities of General Mondragón, who specialized in artillery design, led the family to Spain in 1905, where she met cadet Manuel Rodríguez Lozano, whom she married on August 6, 1913.

Carmen Mondragón turned towards the artists' scene of Mexico City; becoming acquainted with José Vasconcelos and Xavier Villaurrutia.

She became model of several notable painters and photographers, among others posing for some of Diego Rivera's murals, for Tina Modotti, Antonio Garduño, Roberto Montenegro, Matías Santoyo, Edward Weston, and in 1928 for Ignácio Rosas at the Escuela Nacional de Bellas Artes.

At this time she wrote her poems Óptica cerebral, poemas dinámicos (1922) and Calinement je suis dedans (1923), finished several naïve paintings, and composed.

She has been likened to Guadalupe Marín, Antonieta Rivas Mercado, Frida Kahlo, Tina Modotti, Lupe Vélez and María Izquierdo.

In 2019 the Spanish novelist Juan Bonilla published his novel "Totalidad sexual del Cosmos", inspired by the life of Nahui Olin.