You wear a great big cross on your chest and you attend a specialty exhibition for gambling. The big cross on your chest is your badge for being admitted into the exhibition. Everyone at the specialty exhibition has a cross, and everyone is gambling.
You’re not very good at gambling, but you are pretty good at cheating. You hack (はく) the specialty exhibition gambling machines to pay out lots of cash just for you. You hack quickly and quietly, so luckily no one notices that you’ve hacked the system.