There is the old adage to not ...... where you eat, but their is also one that forbidden fruit is the sweetest and that little lady with that hot fit body is certainly sweet, as well as from the sound a woman that loves to fuck.
Your own wife is a real beauty and from your posts likes to play with another couple and swap partners, who if the opportunity was there I doubt many men would turn down the offer of having her. Have you thought about you and your wife having a foursome with this neighbouring couple?