We are a happily married professional type couple in our early 40's and would be considered your typical suburban minivan soccer mom and dad. Kim, my wife, is a teacher, wonderful mother of our two children, my best friend, and a attractive blond. We do not keep any secrets from one another and both consider our marriage very strong. Kim has been open with her favorite fantasy of having sex with a well endowed black man and recently an opportunity to for-fill this fantasy has popped up. Greg, as my wife would describe him, is a handsome black male 26 stationed nearby as a officer in the U.S. Marines. We became friends with him though the local health club and over a period of time Kim confided her fantasy to him. He is more than willing to volunteer himself in satisfying her fantasy. We tentatively picked a date of Sept. 1 which gives Kim and I more time to fully think about all this, plus after this he returns to his home base in San Diego so there is no potential for this becoming a regular thing. My question is should Kim satisfy her fantasy or should we back out?