With a premise such as "stepsister and stepbrother love each other and live under the same roof", I was certainly not expecting much and figured it would just be soft-core porn. Sufficed to say that my conjecture was correct. Spoilers down below. We're treated to a popular, handsome boy that sleeps with every girl that shows interest in him and he does not care about love or anything like that. Nevertheless, he does start to develop feelings for the smart, quiet girl in class(that's actually a huge, kinky degenerate and the daughter of his father's new wife) that really wants to sleep with him. First half isall well and good and to be expected for a manga of this nature. However, I was not prepared for the second half of this series.
Not once, but twice does the main female protagonist cheat in quite a severe way. It might only be her reciprocating their kisses and groping, but it's still too much cheating for my taste.

One positive thing is that the art is good for a series of this nature, drawn well enough and it fits the manga.

If you're the type of person that gets off on cuckolding, this is the series for you. If not, look elsewhere.