it's really not that hard to make friends with kaori. shamelessly optimistic, and almost annoyingly too clever, kaori just wants to be friends with e v e r y o n e. whether they be stranger, criminal, scepter4, homra, or even strain. if it was possible she'd charm the legs of a table.
kaori's basically the "no enemies i'm friends with everyone" type of girl. she's naive like that, but not hopelessly so. she doesn't feel the need to have an enemy unless they do some great horrible wrong to her.
kaori isn't quite sure if she's ready to pursue a romantic relationship, but she would be open to one. it might not work out very well though, seeing as she has to concentrate on school, kendo, and all that good stuff.
obviously, kaori's brother is hayato, a scepter4 clansmen. although she doesn't voice it out loud, she doesn't quite like scepter4, because they've taken her parents, and now her brother away from her. sidenote: if kaori ever became a clansmen, she'd be part of HOMRA, just to get back at her brother and scepter4.