Rangiku probably knows that Hisagi likes her but as a general rule, Rangiku tends to cut short Hisagi's attempt to get involved with her. In omakes, she has dumped cold water all over him by refusing to let him come to a movie with her. She used him as a human shield in a snowball fight then promptly shoved him aside to get back into the fight and used him to cook for Orihime and friends.