This episode starts right away with the results of the second round of poker where Reiko has 3 queens, Nina has a pair of jacks, Sayuri has a pair of 9s, but Kazuki has a lonely 8. Reiko wins the second round. Team Nina feels very defeated at the moment. How can they win at this rate?
Nina knows that their approach of trying to win with 2 pairs is not working. She knows that they need Kazuki to pick a card that either matches Nina's or Sayuri's cards. Reiko discards one card.
Nina then realizes that the suit of the card (hearts, spades, diamonds or clubs) is just as important as the denomination of the card. They would have the highest chance to get a flush if they all have cards from the same suit. Nina discards a 7 of spades and king of clubs. Nina then picks up 2 cards, from her face, it looks like she's got 2 cards from the same suit. Sayuri tries to figure out why Nina would discard both cards, and comes to the conclusion that Nina is aiming for a flush. Sayuri discards a 7 of diamonds and looks at Nina for reassurance. Nina nods and says to herself that they are going for a flush of hearts. Nina and Sayuri both stare down at Kazuki hoping he'll understand, but Kazuki ends up changing cards in panic.