Norae not stand all the voices behind Seola, somehow thinks Seola is innocent and who simply do not always realize that the men around her speak in purely sexual terms.
But Seola is a very beautiful girl and rich (I think I understood). Around her was only interested friendships. Norae is angry with her, from the chapter of the bathroom because she does not respond and let them talk about her that way, and somehow think that the fault is her "open attitude" and she blame for all this.
Evidently jealous, as a friend could easily tell her to be careful, but because she is jealous and now just can not control themselves, Norae does not want to have anything to do with her, because she just does not want to lose control and suffer.
Does not it seem strange and implausible, however, that Norae Seola and they never talked about the declaration of Ji-hwan?
And you think that Seola is really a innocent girl? Maybe she was always gay, and so with all the guys did not go well. Besides, Norae painful past is referred to a boy, for Seola the painful event refers to a girl (even if only "friend")