"My wife and I were staying at her cousins house a few months back after a wedding. On the Sunday morning my wife was cooking a full breakfast and I was still in bed when her cousin walked in in yoga pants looking just like this, and she started looking for something in a wardrobe. Naturally, I was staring at her ass but didn't notice she could see me in a mirror on the back of the door. "Enjoying the view?" she asked. "Er, sorry..." I spluttered. She laughed and, nodding towards my lower body, said "I don't see much movement for someone enjoying the view" She turned and bent right over and started rifling through some drawers. I took this as a green light and jerked off under the covers. She stayed in that position until I finished and as she was walking out she winked at me and said "Think you'd better bring the duvet cover down for a wash, eh?" We're seeing her again over Xmas where I should imagine I'll be getting in her knickers"