A skimpy bikini with matching thigh-highs

Staring at the thin piece of clothing she had removed from the bag, Chelsey tried to make heads or tails of what she was looking at. Spreading it out just right, it seemed to be thin, stringy, orange-colored bikini top, with triangular-shaped patches smaller than her palm where her nipples would be.

Hesitantly reaching further into the bag, she pulled out the bikini's matching bottom half, consisting of an uspide-down, triangle-shaped patch to (barely) cover her pussy that thinned down so quickly it would barely make it to her inner thighs before transforming into a small, negligible string, entirely exposing her plentiful ass to the world, save for a similar triangle patch connecting the waist strings. The top of the patch was also connected by the same tight cross-strings, which looked like they'd barely make it around her hips without snapping.

Now entirely pissed off at her friends, and fully aware that she'd been pranked, Chelsey dug through the bag for any more clothing, only finding a pair of black thigh-highs and some striped black and orange arm-socks.

At the bottom of the bag was a note written by her friends. Not in the mood for their games, she snatched up the paper and hoped, for their sake, it would just instruct her to put her outfit back on and follow them to the party.

It did not.

The front of the note read; "Hey, how d'you like your "costume?" We spend aaages fetting the right measurements, but we think you'll love it~ Make sure to wear just the costume, no cheating and wearing your plain old undies. We'll know if you do~ (not like you have much else to put on anyways~"

Confused, Chelsey wondered what the note meant by "not much else to wear..." Until she turned around just in time to see her costume and candy bag being swiped from the top of the door.

Yelling for the thief to stop, Penny's trademark maniacal prank-fueled laughter was the only response, and before Chelsey could even step outside of the stall, the door to the bathroom was already shut in her friend's wake.

Knowing she would never catch up with Penny, her college track team's fastest sprinter, she sighed and returned to the note in her hand.

"Not like I could chase after her in this outfit anyways..." Chelsey thought.

Flipping the note over, praying that there was some explanation on the other side, she only found Penny's poor penmanship, "Heeeyyyy! so! Y'know how we mentioned we'd be hittin a few more houses before goin to the party? We alredy got those ones all warmed up fors U, so we went on ahead to the party! NOW! And this is VERY IMPORTANT! You have to keep this costume on the whole time, Well know if U put anythin else on! Good luck bestie, have fun w/ our halloween trick! Hahaha! -With love, Penny and Vanessa"

Staring dumbfounded at the note, Chelsey felt her face grow red from both embarrassment and anger. Those two were always pranking her in one way or another, but they'd never gone this far before...

Did they really intend for her to wear... This outside? Nonetheless go trick-or-treating in it?