Read manga: Bunbetsu To Takan

manga
Summary:

From Jshoujo:Aya has a great boyfriend Kento who treasures her a lot. But she is also attracted to Kento's older brother, who has a twisted personality. How come she can't stay away from him and she goes so far to cheat on her boyfriend? Will Aya's sense prevails over her sensibility?Includes two side stories.