They have made Misaki too thick. Or actually I don't even know if it should be called thickness because she has heard confessions from both of the guys so it's a nobrainer why they would be at each other's throats over her attention. But then again, she's actually still denying any of the confessions could be true and not just jokes, so who knows...
I hope one of the other workers at the cafe really kicked her ass, figuratively speaking, to explain nobody would go as far as Usui as a joke.