Demetrio was born on 14 May 1932 in Pachuca. He was born without arms. From childhood he had to perform certain tasks with his feet. In 1950, he started painting with his right foot and he was pretty good at it from the beginning. In 1964, Demetrio was granted a scholarship by the association. This gave him the opportunity to dedicate himself completely to painting.
Demetrio paints in the modern Mexican school of art. He devotes his painting to the landscapes of his home country. With great realism and clarity he depicts the warmth of his surroundings. People of his country, is another favourite subject of his.