It's time for you to be sent to another world, one currently under threat by the ancient Demon Lord. Naturally, as you are the Hero, it's up to you, along with a helpful group of legendary samurai, to save the world!
Which you will do by playing the ancient game of Koi Koi!
... Wait, isn't that a card game?
Note: This storygame doesn't diverge as much as most story-wise, as a large portion of it is the card game.