Mr. Lopez is the father of Ernesto, Leta Lopez-Wilkinson and Luis Lopez and the ex-husband to Adriana Yanira Lopez. He served in the United States Marine Corps, and, at an unknown point, left them for a new wife and family in the Midwest. According to Leta, however, Mr. Lopez left his new family in the Midwest as well. Despite the fact that Mr. Lopez abandoned his wife and three children, Luis still has three pictures of him on the walls in his apartment. Mr. Lopez bears a striking resemblance to Luis, even down to the goatee.
Leta informs Luis to get her children's pictures up and remove their father's pictures, calling their father an "asshole". Luis and Leta have a strong disliking for their father, but Ernesto appears to be indifferent.
- One of the medals on Mr. Lopez's chest is the Navy Cross, which is the second highest award for combat a Marine can earn.
- The Eagle Globe and Anchor on Mr. Lopez's pocket is on the right side, but it should be on the left under the U.S. Marine Name Tape.
- Mr. Lopez has no rank insignia in any of his uniforms in the pictures, which would make him a Private at least.
- Somewhat strangely, even though Mr. Lopez left his family when his children were young, Luis has a recent picture of him in Marine Corps MARPATS, which didn't start circulating in the Marine Corps until 2001-2004.
- In one of the photographs Mr. Lopez is wearing a navy blue great coat with his dress blues. This color coat is only authorized for members of the Silent Drill Platoon.
- Sometimes, when Luis is drunk, he might exclaim "Apparently my daddy was a drunk; good thing I'm not!".
- In the game, Luis' mother, Adriana Yanira Lopez, mentions Mr. Lopez and said that Luis is "just like his father," when Luis was treating his mother with hardly any respect in Momma's Boy.