This is Aya, the oldest of the (100% blood-related) sisters in Imouto Paradise. She is in many ways the perfect imouto. She cooks, cleans, and is receptive to her brother’s (your) lechery. As the maternal figure of the household, the other sisters look up to her to do all the daily chores that they can’t be arsed to do because they’re too busy trying to win their brother’s (perverted) attention.
Normally I’d expect the heroine-type to be a pure and virtuous maiden. However, I believe the naked apron proves she is anything but.
In fact, she is surprisingly lusty. She might not be as kinky as Michika, but she’s definitely eager to please beloved Nii-san.
But she also knows that sharing is caring. She would not be so rude as to deny her sisters their fair share of Nii-san. She understands that sexy time can be, and indeed SHOULD BE, fun for the whole family.