From Lovelipop Scans:

Due to living with her 3 brothers and father for so long, 2nd year Mizumori Hidarishita has come to hate all guys! Against all odds, she encounters Koizumi Ikurou, an avid girl-hater because of his troublesome sister. Tired of being pursued by the opposite gender, they both seek refuge in holding onto their beliefs, but what happens when Mizumori's dream world is torn apart?