Well I disagree, because the pretty much ever-present thing of incest games is the mom (or big sister) progress - at first she's just close to you, you perv on her, she pervs on you a little bit and feels disgusted, she pulls back, eventually something happens and she comes to terms with it a little bit, then you push her, etc. etc. and it ends with her admitting her love for you and then pound town. Then the dev cuts the game because he's utterly bored with it.
Milfy city pretty much starts at the end, with Linda, and progresses from there. Caroline is also outside the cliche, a little, because she's not your usual tsundere big sister who you bring around through showing her who's boss.