My wife and her boyfriend used to meet on a Monday after work. One particular morning I had seen her get dressed to go to work that day and saw that she had chosen to wear a pair of her sexy frilly lacy knickers. I watched as she freshened up her makeup ready to meet him. No doubt by now my wife’s frilly knickers would be sopping wet in anticipation of the dam good shagging she knew she was about to get from her work colleague. I bet during the day he had got a hard on as he ogled my wife at work knowing that now with my semi approval, he was going to give her a dam good shagging later. As usual I watched her ‘tart herself up’ lipstick, eye shadow, and as usual got a real boner as I imagined what he would soon be doing to my wife I loved so much. At the time, that was why I found the whole thing very strange. I am older and wiser now and understand this reaction is not uncommon. Anyway, his car pulled up and she was out of the front door and into his car. I couldn’t wait to get my dick out, and wank myself off. I went back upstairs to the bedroom, found the pair of knickers in the linen basket she had been wearing the day before and wanked myself off as I sniffed them. I came almost immediately. Ever since then I have been an avid knicker sniffer whenever I got the chance. Later, I would hear the car door close as she was dropped off and she would come back into the house with her tights in her hand and put them in the basket to be washed. I was horny again by now, so when she went back downstairs, With trembling hands I retrieved them, and wanked myself off again, this time sniffing the gusset which smelt of her sex. It was fantastic, I couldn’t help myself, I gave a groan, much louder than I intended and ejaculated powerfully. My wife and I had now stopped having sex together. During a heart to heart discussion she and I had where I asked for more details, she reluctantly told me that the first time they ‘made love’ he gave her the longest orgasm she had ever had. After pressing her for more info, she went on to say he normally makes her cum 2 or sometimes 3 times when they meet. It was clear he was not just shagging my wife, but giving her a bloody good servicing in the process. I became more and more obsessed with thinking about my wife getting shagged. I became totally fixated and used to masturbate as I imagined him shagging her. I was becoming immensely turned on by the smell from her soiled panties after her session with Graham and used her worn knickers to sniff as I wanked myself off as I fantasised about them snogging, his hand up her skirt and pulling her tights and panties off then fucking her as she gasps in pleasure. I also started sniffing the tights she had been wearing all day at work and wanking myself off sniffing these as well. I was wondering what was wrong with me and feeling very guilty about what I was doing.