I've always been attracted to my wife's youngest sister; great looks and fun personality, we really like each other. Recently, she visited and we happened to be alone. She confided that she'd asked my wife about sex in general and with me in particular. She said that she trusted me and asked if I could satisfy her curiosity without telling my wife. It began with me showing her how it really looked and felt. We did a lot of groping and kissing, but it didn't go past that. My favorite part was spanking her full, round bottom; seems the two sisters have some parts and interests that are strikingly similar!