This happened a few years ago with an exgf; I'm surprised I haven't typed it up before now actually as it was a good experience.
My GF at the time was fully aware of my fetish and quite happy to play along with it as she found it fun too.
I was lying on her bed resting one Saturday morning as she was getting dressed. She'd just gotten out of a the shower was applying some kind of moisturizing cream called Body Butter. As I watched her apply it to her torso I said
"I bet that stuff would make your skin really slippery and very ticklish"
She turned to me and replied "it probably would, yes" with a bit of a cheeky smile.
"I think I should tie you up and find out" I winked back at her.
"How about this" she replied, "I tie YOU up and find out how ticklish it makes YOU?"
I playfully joked that wasn't the same thing, but she said "Nope, you want to find out how ticklish it makes someone, you can try it on yourself".
"Finnnnneeeeee" I pretended to resist but she know I would enjoy it either way.
She climbed up onto the bed with me, pushing me onto my back and climbing on top of my stomach.
"Arms up" she said and reached over to the bedside table removing the ankle/wrist restraints we kept in there. They were simple in design, just loops of cord that could be pulled tight and knotted around the bed frame.
She secured my wrists up above my head and my ankles to the base of the bed. I could wriggle but I couldn't escape from them.
Once tied, she open the tube and squirted the cream into her hands; it had a strong smell of vanilla and almonds and was quite thick overall. Leaning forward, she smeared it from my elbows down towards my armpits
"AH HAAA" I laughed out
"That doesn't count" she giggled. "I've not even started tickling you yet".
"I know" I replied, "it's just bad under my arms"
"I better apply extra there then" she said
She squirted more cream into my armpits and down my sides. I giggled and squirmed as she was doing it and tried to bite my lips.
"Ready?" she asked
"Sure" I said hestitating
"Okay, GO"
Her fingernails slide across my skin with barely any friction at all. In an instant I screamed out with a "FuucC HAAHA" and yanked at the restraints pulling my wrists. As she traced her fingertips over my armpits I really lost it. Trying to sit up to no avail, laughing and trying to ask her to stop
After a couple of seconds she ceased and let me catch my breath.
"If you can last ten seconds without asking me to stop, I'll let you go" she said. "But every time you do, we start again from ten. Deal?"
"I don't know if I can last that long" I told her
"Well I'm not letting you go until you've done the whole ten seconds" she replied with a very cheeky look in her eyes.
"Fine" I laughed, "I guess so"
"Right, are you ready? GO"
She began tickling my armpits straight away this time and I just lost it. Thrashing left and right, pulling against the cords
"Teeeeeennnnnnn" she counted
"Haha! That's not haha, not real counting haahaa" I tried to get out
"Niiiinnnneeee"
She slid her fingers down my ribs and across my stomach. I bucked up and down, nearly throwing her off but she held on tightly with her legs.
Moving her fingers back up my ribs she returned to my armpits
"Please!!!" I begged "Pleeeeaaaassseeee hahah"
"Siiiiiixxxxx" she counted
By this point I was broken and couldn't even beg. She must have known I was struggling as she reached five and stopped.
"That was WAY longer than ten seconds" I said as I gasped for air
"Nope, it was only five" she laughed. You own me another five seconds
"I don't know if I can"
"Turn over" She asked
Sitting up she motioned for me to turn. This twisted the restraints and pulled them tighter so I was more immobile that before.
She spun herself around and lay her full weight on the back of my legs
"If you can do five more seconds on your feet I'll let you out".
"I feel I've already done more than ten" I playfully argued with her.
"Feet or armpits, your choice" she replied
"...fine...feet" I said
She started massaging the lotion onto the soles of my feet. I began to say "that actually feels quite nice", but before I was able to finish she dragged her fingernails over the sole of my foot and I jumped, laughing immediately.
"HA NOOO" I screamed out.
She dragged her fingers up and down my soles - my heels were surprisingly sensitive - but when she pushed between my toes I really lost it
"NO NO STOP HAHAHA" I screamed
"Fiiiveeeee" she counted
"STOPPAAAHHAA"
"Fouuuuurrrr"
By this point I was in silent laughter again. She continued to push her fingers in between my toes as it got such a huge reaction. Every 'second' she counted felt life a lifetime.
Eventually she reached one and stopped. I managed to start to catch my breath and regain composure.
"That was awful" I said
"and you wanted to do that to me" she laughed.
She untied me and left me there for a moment while she finished getting dressed. Unfortunately I never got to get revenge on her for this one. Still a fun memory though.
My GF at the time was fully aware of my fetish and quite happy to play along with it as she found it fun too.
I was lying on her bed resting one Saturday morning as she was getting dressed. She'd just gotten out of a the shower was applying some kind of moisturizing cream called Body Butter. As I watched her apply it to her torso I said
"I bet that stuff would make your skin really slippery and very ticklish"
She turned to me and replied "it probably would, yes" with a bit of a cheeky smile.
"I think I should tie you up and find out" I winked back at her.
"How about this" she replied, "I tie YOU up and find out how ticklish it makes YOU?"
I playfully joked that wasn't the same thing, but she said "Nope, you want to find out how ticklish it makes someone, you can try it on yourself".
"Finnnnneeeeee" I pretended to resist but she know I would enjoy it either way.
She climbed up onto the bed with me, pushing me onto my back and climbing on top of my stomach.
"Arms up" she said and reached over to the bedside table removing the ankle/wrist restraints we kept in there. They were simple in design, just loops of cord that could be pulled tight and knotted around the bed frame.
She secured my wrists up above my head and my ankles to the base of the bed. I could wriggle but I couldn't escape from them.
Once tied, she open the tube and squirted the cream into her hands; it had a strong smell of vanilla and almonds and was quite thick overall. Leaning forward, she smeared it from my elbows down towards my armpits
"AH HAAA" I laughed out
"That doesn't count" she giggled. "I've not even started tickling you yet".
"I know" I replied, "it's just bad under my arms"
"I better apply extra there then" she said
She squirted more cream into my armpits and down my sides. I giggled and squirmed as she was doing it and tried to bite my lips.
"Ready?" she asked
"Sure" I said hestitating
"Okay, GO"
Her fingernails slide across my skin with barely any friction at all. In an instant I screamed out with a "FuucC HAAHA" and yanked at the restraints pulling my wrists. As she traced her fingertips over my armpits I really lost it. Trying to sit up to no avail, laughing and trying to ask her to stop
After a couple of seconds she ceased and let me catch my breath.
"If you can last ten seconds without asking me to stop, I'll let you go" she said. "But every time you do, we start again from ten. Deal?"
"I don't know if I can last that long" I told her
"Well I'm not letting you go until you've done the whole ten seconds" she replied with a very cheeky look in her eyes.
"Fine" I laughed, "I guess so"
"Right, are you ready? GO"
She began tickling my armpits straight away this time and I just lost it. Thrashing left and right, pulling against the cords
"Teeeeeennnnnnn" she counted
"Haha! That's not haha, not real counting haahaa" I tried to get out
"Niiiinnnneeee"
She slid her fingers down my ribs and across my stomach. I bucked up and down, nearly throwing her off but she held on tightly with her legs.
Moving her fingers back up my ribs she returned to my armpits
"Please!!!" I begged "Pleeeeaaaassseeee hahah"
"Siiiiiixxxxx" she counted
By this point I was broken and couldn't even beg. She must have known I was struggling as she reached five and stopped.
"That was WAY longer than ten seconds" I said as I gasped for air
"Nope, it was only five" she laughed. You own me another five seconds
"I don't know if I can"
"Turn over" She asked
Sitting up she motioned for me to turn. This twisted the restraints and pulled them tighter so I was more immobile that before.
She spun herself around and lay her full weight on the back of my legs
"If you can do five more seconds on your feet I'll let you out".
"I feel I've already done more than ten" I playfully argued with her.
"Feet or armpits, your choice" she replied
"...fine...feet" I said
She started massaging the lotion onto the soles of my feet. I began to say "that actually feels quite nice", but before I was able to finish she dragged her fingernails over the sole of my foot and I jumped, laughing immediately.
"HA NOOO" I screamed out.
She dragged her fingers up and down my soles - my heels were surprisingly sensitive - but when she pushed between my toes I really lost it
"NO NO STOP HAHAHA" I screamed
"Fiiiveeeee" she counted
"STOPPAAAHHAA"
"Fouuuuurrrr"
By this point I was in silent laughter again. She continued to push her fingers in between my toes as it got such a huge reaction. Every 'second' she counted felt life a lifetime.
Eventually she reached one and stopped. I managed to start to catch my breath and regain composure.
"That was awful" I said
"and you wanted to do that to me" she laughed.
She untied me and left me there for a moment while she finished getting dressed. Unfortunately I never got to get revenge on her for this one. Still a fun memory though.
Thanks for sharing the experience with us. 
