Following her loss, Mary becomes a Pet. Yumeko, whose name has been spread all over the school for having beat Mary on her first day after her transfer, is challenged to a Double Concentration game by Itsuki Sumeragi, the daughter of the CEO of Japan's top toy company and a first-year member of the Student Council, famed for having never lost at a card game before. For this gamble, Itsuki uses two decks of cards "Radcliffe" made by her father's company and wins 20 million yen from Yumeko in a close match...