Gambler's game

Protagonist Kazuki has been getting on well with childhood friend Ayano. When they receive an invitation to a popular resort, Kazuki is hesitant, but Ayano insists they go. While enjoying the luxurious hotel, the sender of the invitation appears; the owner of the hotel, and the organizer of the "gambler's game". It seems Kazuki's father once racked up a huge debt, and that debt has been pushed onto him. Kazuki is forced into the game, and since he has no money, his only collateral is Ayano. Can he win out, pay off the debt, and escape without his childhood friend getting cucked?