@aatlass
Teenage girls? Yeah, some are hella passive aggressive. Hell I experienced this exact situation back when I was in high school, though admittedly not to this serious of a degree.
Friend A really wanted this boy's attention at a party, but the boy had zero interest in A and instead was all over Friend B. B had zero interest in the boy, and knew A really wanted him, and just desperately but politely tried to reject him the whole time.
A completely blacklisted B, blamed her for the whole thing, because teenagers are hormonal and immature. No bullying happened, probably because most of us were like "A, dude, B wanted nothin to do with this guy, he just wasn't that into you so walk away.", but it did completely ruin their friendship beyond all repair and it was such a stupid thing to get mad about.
It's heavily exaggerated because this is manga, of course, but it's not so much that "this is what women are like?" but rather, this is what some immature teenagers are like because being a teenager sucks.
It's kinda like the movie "Mean Girls". It's a heavily exaggerated comedy, but part of the reason it's so funny is because it has nods to reality.