Neltair Rebés Abreu is a Brazilian cartoonist, who works under the pen name Santiago. Born in Santiago, he moved to Porto Alegre in 1970, where he worked as a technical illustrator in the industry. He got his nickname Santiago while attending the Faculty of Architecture, and has used it since for his work as a cartoonist to escape the political censorship of the time.
Santiago's first work was published in O Quadrão, the humor supplement of the newspaper Folha a Manhã. He eventually became a professional contributor to the paper's regular pages, and was an editor for nine years until the paper's closure in 1980. He has also contributed to Correio do Povo, Coojornal, Pasquim, Estado de S. Paulo, Bundas, O Pasquim 21 and Jornal do Comércio.
He is the author of several books, including 'Causu do Santiago', a large collection of autobiographical comic stories, published by Zarabatana Books in 2014. His drawings appeared in the paper Extra Classe, and magazine Le Monde Diplomatique.