- B-ko is first introduced when a school mate of her and A-ya talks to latter about a rumor that would include B-ko and the question if she has a boyfriend or not. Although A-ya denies to have heard anything about this rumor, he says he has heard another one about her, so he tells their school mate a rumor about B-ko having an impostor. The story goes around B-ko, who walked into the opposite direction of her home after school and was seen by one of her classmates through a bus window. The curious classmate sent her a text message, asking what she is doing at the moment, to which B-ko replied that she would be at home, studying. According to A-ya's rumor, her neighbor witnessed that she was at home this day.
- The rumor spreads in the school during the morning and eventually B-ko confronts A-ya with it, telling him angrily that he should not start any fake stories about her. D-ne, a girl that visits their school as well, comments how she likes B-ko's dual nature, as she appears to be cute and nice at the one moment, and angry and wild in the next one. C-ta, another school mate who is with them in the room, says that B-ko always had a soft spot for D-ne and how there really sometimes seem to be two different versions of her, after she responded to her that it sounds like she was telling her that she has a split personality.
- When A-ya tells them about how he constantly feels like he is being watched by someone, although no one is around, she suggests that if Merry-San was the cause, it would have to do with a phone. As he mentions that the cause could be related to the Bookmark of Demise, she disagrees with him, saying that this is not possible, as they failed to obtain it. This ultimately leads to A-ya demanding that they should try it again.