Kuro Kagami is also Rin's frequent "partner in crime" due to their comparable levels of sexual knowledge. She is openly contemptuous of Aoki due to his lack of sexual experience, naïveté, inability to consistently enforce discipline in the classroom, and her belief that he is a pervert, lolicon, and rival for Rin's affection, and often verbally — and sometimes even physically — abuses him. The apparent wealth of the Kagami family allows Kuro to indulge her obsession with following the latest, expensive fashion trends, and she often wears clothing in the Gothic Lolita style, sometimes combined with nekomimi ears and tail. Though others may have the impression that she is a show off, bad apple, or spoiled brat, she has managed to befriend both Rin and Mimi and is very dedicated to and protective of them both. Much to the surprise and confusion of just about everyone, Kuro eventually comes to idolize and develop something of a crush on Sae Shirai, possibly due to their similar personalities and temperaments.
Wikipedia