I've already lived my fantasy - about 40 years ago! I'd just like one more go-around from the opposite side of the age and experience spectrum.
I was studying (really!) with my girl friend when we were both juniors in high school when her 22 year old sister came home. She had been drinking and was horny as hell and there I (an innocent young man!) was. She and my girl friend started taking my shirt off and when I resisted and we started wrestling the older sister discovered I was ticklish. She was incredibly strong (and I was a wimp) and they simply over-powered me and tied my arms up to two legs of a very heavy couch with two towels. Once I was secure, they finished taking my shirt off and started tickling the hell out of me.
When the older sister asked me if my feet were ticklish I really started to panic. I thought I was "saved by the bell" when the doorbell rang before she even started to take my shoes off, but no such luck - it was two friends of the younger sister, both of which I knew from school! When they got involved and started taking my shoes off, I started struggling so hard I actually started moving the couch, so the big sister went scouting for a better place to tie me up.
What she found was some rope and a place under the basement stairs where they could tie me up standing. I was so exhausted by then they really didn't have much problem with that part, but I did start fighting again when they started trying to take my shoes off again. They were afraid someone would get hurt trying to hold my legs while someone else was tickling my feet. Her solution for that was to get two kitchecn chairs and tie my legs to the seats with my feet sticking out through the slats in the back of the chairs. Not only did that expose almost every part of my body, one of them suggested taking my pants off before they did that!
The next hour or so just about destroyed me. They finally realized I was at the "end of my rope" and finally released me and let me lay down in the older sister's bed (which was downstairs). I promtly fell asleep. The next morning when I woke up I was tied to the bed spread eagled and now my underwear were gone too, but that is a different story.