My best friend's mom who I will call Grace, was around 50 at the time. She was about 5'1' tall with long auburn hair. Grace seemed to me at the time to ooze sex. She always wore tight jumpers emphasising her generous tits, and skirts which in all honesty were really a little short for a woman of her age.
It was her short skirts that got me hooked on my up-skirt fetish. I would often visit my friend and if he was working late, Grace would invite me in to wait. She had a favourite chair where she always sat and from my position I was able to catch a glimpse up her skirt. She wore tan stockings and I could often see the dark stocking tops, white thighs and her knickers.
I would fantasize about Grace at night and used to wank frequently remembering the up-skirt views.
It was shortly after this that I discovered where Grace kept her linen basket. I was able to sort through and find her knickers. They were always silky and on the first occasion I took a pair and rushed home to wank. I breathed in the delicious aroma of her cunt and experienced a mind blowing orgasm, cum squirting all over my stomach and chest.
I began wanking every night and morning (and sometimes during the day) using Grace's knickers.
Eventually her aroma faded and at this time I would wrap her knickers around my aching cock and wank until I spurted into them.
I then managed to 'exchange' her knickers for a new pair.
This looking up her skirt and wanking into her knickers continued for several months until my relationship with my friend ended,
I've no idea whether Grace ever suspected what I did, but even now I sometimes wank remembering those times.