Takashi's parents remarried and he ends up living with his stepsister.
He thought it would be awkward to live with a girl, even though she was his stepsister, but he was surprised when he saw her.
Her name was Alice, a beautiful girl from Northern Europe.
While Takashi was happy to have a beautiful stepsister, her overly large breasts made him feel uneasy.
However, seeing Alice trying to fit in with the family, Takashi suppressed his wicked feelings and treated her as his stepbrother.
However, one day, when he saw Alice naked, Takashi's wall of reason collapsed.
タカシは親が再婚したことで義妹と一緒に暮らすことになる。
義理の妹とはいえ女の子と一緒に暮らすのは気まずいのではないかと思っていたが義妹の姿を見て驚く。
名前はアリスといって北欧出身の綺麗な女の子だ。
綺麗な義妹ができて嬉しい気持ちがある一方、彼女の大きすぎる胸はタカシの気持ちをかき乱すのであった。
だがアリスの家族になじもうとする姿を見てタカシはよこしまな気持ちを押さえながら義兄として接していくのであった。
しかし、ある日アリスの裸を見てしまったことでタカシの理性の壁は崩壊してしまうのであった。
