Determined to become a winner at Hyakkaou Academy and free Tsuzura from her "housepet" status, Mary devised a plan to open her own gambling den and become its master. To do so, she targeted the least popular gambling den in the school, run by the Literary Club under the leadership of Yukimi Togakushi (Minori Hagiwara). Mary and her group stormed the club, only to encounter unexpected visitors: the Student Council Disciplinary Committee Chair, Sachiko Juraku (Hajime Nagai), and her "housepet," Mikura Sado (Mirei Sasaki). They had come to seize the Literary Club's gambling den due to unpaid usage fees. In the midst of this, Mary made a shocking proposal to Sachiko, offering to take over the gambling den herself. Intrigued by her boldness, Sachiko agreed, but set a condition: Mary and Yukimi would face off in a gamble, with the loser taking on the Literary Club's debts. Thus, Mary's second battle began.