It’s Christmas time again, and Kyouka invites everyone in the class to her family’s grand Christmas party. Keiichi tells Kyouka to invite Kosuda over as well, much to her shock. Yamada has no interest in it at first, but gets lured in because of this “Secret Room” Misato is talking about. Kyouka has difficulty inviting her enemy Yamada, but it was solved when the latter demanded an invitation from her. The class, including their teachers, while awed by the party’s grandness, finds it difficult to mingle with the rich people Kyouka also invited–save for Takeshita, who draws attention; and Misato, who lunges for Keiichi at will. Kyouka hears of this “Secret Room” thing from Misato, and she begins to suspect it could be her secret “Brother Room.” Kyouka’s panic arouses Keiichi’s attention, so, as a result, she tells Yamada and Kosuda to get going, although letting her go seems to be a mistake.