@Pony feet  
Pretty sure she was in a chair to start out and Lucky Charm tackled her to the floor once she nodded off.

@RAMMSTEIN45
 
@RAMMSTEIN45  
Forget the Chum Bucket! This is personal!  
*Takes Rarity’s boot off and licks her foot slowly  
*Rarity screams in agony

@Background Pony #784A
 
Like she is laying on her back while he massages her foot and once she fell asleep. Only to be interrupted with a tickle out of no where. XD

For some odd reason, i always like to imagine this all started with this ‘Lucky Charm’ character offering to massage Rarity’s feet for her. she felt so relaxed by the massage that she fell asleep, giving Lucky the chance to….uh…..do this.

@orbsah
 
My rank on that is very similar. Here are my ranks and reasoning why.
 
Twilight- She was smacking her leg up and down on the floor. That is easy to tell she is really sensitive when it comes to tickles. Even if he was holding the other leg back, she would somehow get it free to smack it on the floor.
 
Fluttershy- That face expression and how she is putting her hands straight up pretty much tells that her feet aren’t made to be tickled. It’s too much for a shy thing like her.
 
AppleJack- Sure she was tied down, but her face expression is able to tell how much it tickles for her.
 
Rarity- For someone who isn’t tied down and has one leg free, she is staying really still while being tickled.
 
Pinkie- She is the only one not tearing up and seems to actually enjoying it.
 
Sunset- She doesn’t even seemed or looked like she was being tickled in the slightest. She seemed more disturbed and shocked then anything.

Based on their expressions, from most ticklish to the least ticklish:
 
Twilight  
Fluttershy  
Rarity  
Applejack  
Pinkie  
Sunset

@Miss Shy
 
Every picture that is like this is a Fry Cook Games reference I guess.

@RAMMSTEIN45  
We’re gonna make this joke every time, aren’t we?

@RAMMSTEIN45  
I don’t really see this as a Fry Cook Games reference, but it’s still cute. :)

Do another fluttershy one :3 great work i always love to see your artwork <3

“Forget the Chum Bucket! This is personal!”