Yumeko is challenged to a game of Concentration by Itsuki Sumeragi, the daughter of a toy company CEO. Itsuki uses two decks of cards made by her father’s company and wins 20 Million Yen from Yumeko in a close match. Yumeko demands a rematch to get it back and Itsuki accepts under the condition that she bets her fingernails and toenails. Itsuki deals from her two decks again, confident that her cheating style of using heat-activated patterns in the cards will help her win. However, Yumeko picks up on her scheme and wins on the first turn, remarking that Itsuki would have won if she used fresh cards. Afterwards, Kirari and her student council members gather with the objective of eliminating Yumeko. Yumeko finds herself invited to the club room of the Traditional Culture Research Society, just as Mary loses a high-stakes bet.