Raul Osiel Marroquin Reyes, born in Tampico, Tamaulipas around 1981, killed four men in Mexico City between October and December 2005: Jonathan Razo Ayala, Ricardo Lopez Hernandez, Armando Rivas Perez and Victor Angel Ivan Gutierrez Balderas. He picked the men up in gay bars, held them for ransom from their families, tortured them and strangled them with a ligature.
He was arrested on January 23, 2006 and told investigators he had, in his words, snuffed out four homosexuals who were in some way affecting society. He was convicted and sentenced to 300 years in prison on September 4, 2008, a nominal figure under Mexican sentencing practice rather than a term any prisoner serves. Mexican reporting called him el sadico, the sadist.
The kidnapping-for-ransom element distinguishes the case from most entries here: the killings followed extortion attempts rather than preceding them.