Given the following context:

The film opens with a news broadcast about a teenager named Jason Jackson being shot outside of the Monte Vista High School dance lock-in. Jason tells the story from the beginning, starting with him trying to get into the most popular dance clique in school, The Ranger$ (Langston Higgins, Julian Goins, and Dashawn Blanks). They say he has to pass the initiation of getting a pair of panties from one of the Sweet Gyrls by midnight. Jason then decides that he is going to attempt to get a pair of panties from his longtime crush Anastacia (Kristinia DeBarge during the school's lock-in.
Meanwhile, Day Day, one of the Ranger$ and Jason's older cousin owes Anastacia's eldest brother Junior $2,000 by midnight due to Day Day's father Darren telling Junior that Day Day would have his money after losing to him in a game of dominoes. In his English class, Jason gives Anastacia a poem he wrote about her after she forgets to do the homework assignment expect the teacher makes her read it in front of the class which everyone including Anastacia finds to be very great. After school is over, Anastacia gives Jason her number so they can write a song together sometime.
Another subplot of the film follows two police officers Officer P'eniss and Lagney, who are chasing down the New Boyz who are on their way to the lock-in but get caught with weed brownies and "grape juice", which Officer Lagney consumes.
At the school dance lock-in, Jason, Anastacia, the Ranger$, and Sweet Gyrls play "7 Minutes in Heaven", but when it is Jason and Anastacia's turn, she tells him that she already knows his plan and they decide to just stay friends. They later compete in a talent show to win $2,000 but when it comes to the Ranger$' performance, Jason finally beats his fear and raps to help them win the money. However, the Sweet Gyrls end up winning the prize money.

answer the following question:

Who lost a game of dominoes? 

Day Day