Keita has two older step-sisters, Ako and Riko, but since they aren't related by blood, they love him in a lustful way. After a mishap at school, Ako and Riko finally confess their love to him. Keita dislikes the thought of seeing them other then brother and sister, but as he tries to enter the same school as his sisters, he slowly becomes attracted to them.
Story average (3/5) : The story doesn't make sense. And believe me, the only logical part is, ironically, that the guy is attracted to his step-sisters, THAT is understandable. But anything else in the anime is weird. The situation are simply not logical. Maybe it's for comedy effect, but I don't sense it either.
Dialogue good (4/5) : a lot and a lot of ecchi/sex related dialogue in the first 2 episodes which is OK for an ecchi anime of this kind.
Animation good (4/5) : it's not as good as Angel Beat but it's "watchable"
Entertainment good (4/5) : the ecchi parts are entertaining. french kisses, sex simulation, "embarassing" situation and wierd parents who acually are mad at their boy because he thinks his step sisters are "sisters" before "girls?" lol !