Keiichi was entrusted with major investments at a foreign investment fund. His colleague, Oki, was both his best friend and his rival. However, one day, Keiichi suffered a massive loss and found himself backed into a corner. Seeing this, Oki proposed a certain game to him. The bet was simple: Oki would try to seduce Keiichi's wife, Mayu. If she fell for him, Oki would win; if she didn't, Oki would hand over the deal to Keiichi. Keiichi was absolutely confident that Mayu loved him. But once the game began, Oki used his skillful techniques to disturb Mayu's heart and began to steal her away...