Everyone has said it by now, but Ami is kind of an asshole lol. However I did think that part where she says Rei looked "totally stunning" was really sweet.
Ami also stood up for Rei against the creep while not realizing it was Rei, so maybe she's not exactly a "bad" person. I'll definitely stick around and keep reading to see how this ends.
That's what makes it even more painful, imo. Rei gets swept away every time Ami shows a modicum of chivalry, or is slightly considerate, just to IMMEDIATELY do a complete 180° and do the most assholish things.
Makes me go back to what she said on ch.1, she really would've been better off if Ami just rejected her outright.