The Cat Burglar -Trade-

The stronghold was set in the middle of a mountain range.  It was guarded around the clock, and many high-tech security measures guarded the treasure within.  It almost seemed like a challenge for thieves to come and try their luck.

Of course, someone took the challenge.

A black figure coasted across the night sky, directly towards the stronghold.  It was none other than the elastic black cat known as Blinkie.  She'd molded her arms and hands into a hang glider for the trip, and was enjoying the sensation of the air rushing over, under, and around her.

Wheeeeeee!

As she passed over the stronghold, Blinkie retracted her arms back to their normal shape, dropping down onto the roof.  The impact briefly squashed her down to a fraction of her normal height, but she popped back without difficulty.

Alright, here I am.  I just have to sneak in, steal the diamond, and get out.

Blinkie scanned the roof for potential entrances.  A circular hatch caught her eye, and she meandered over and gave it a try, only to discover it was locked.

That didn't discourage this elastic cat so easily, though.

Getting an idea, she crouched down on the side with the hinges, then literally stretched her arm over and knocked firmly on the hatch.

Seconds later, a zebra in a security guard's uniform shoved the hatch open and peered out.

"Who's th--"

That was all he got to say before something round and black slammed down on top of him.  Blinkie had stretched out her lower body and assaulted the guard with her rear end.

As soon as she felt the floor stop her, Blinkie retracted her rear and admired her handiwork.  The zebra was now a large round sticker on her posterior.  Leaving him there for the moment, she climbed down into the hatch herself.

The area down below turned out to be a short tunnel leading to a single door.  Blinkie paced down the tunnel, deliberately swaying her hips with every step for no real reason other than to give her "passenger" a bit of a ride.

Being a cautious sort, the thief peeked before trying the door.  It seemed to lead to the guards' quarters.  Thankfully, they all seemed to be asleep, so she silently turned the knob and pulled the door open.

The lights were all out, and the room was filled with the snoring of about half a dozen guards.  Blinkie started tiptoeing through the room, making absolutely no noise on her way to the door on the other end of the room...

BANG!

...until the door slammed shut behind her.

All the guards jumped up at the noise, looking around for its cause.  Flashlight beams circled the area, but none of them found the literal cat burglar lurking in the room.  One by one, the guards went back to sleep, one of them muttering something about getting that stupid door fixed.

Blinkie breathed a sigh of relief as she climbed out of the (thankfully otherwise empty) trash can she'd squeezed herself into at the last second.  She managed to get to the other door without further incident.

The next room in the base was a straight hallway.  Having watched enough spy thrillers to know what this one was about, Blinkie took a fog machine out of nowhere in particular and plugged it in.  Minutes later, the room was filled with mist, revealing the many previously invisible lasers that crisscrossed the hallway.

This should be easy.

Stretching herself out at the waist, Blinkie planted her forepaws in a safe spot between the lasers, then let her rear snap back to her.  She then extended her lower body in the same way, touching down in another safe spot.  She repeated this unorthodox maneuver until she was on the other side of the lasers.

Now in the clear, the cat approached the vault door in front of her, sealed by a single rotating handle.  She twisted herself around the handle a few times for leverage, then grabbed it and pulled.  At first it resisted, but after a moment it began to budge, then rotated freely.

Yes!

Blinkie pulled the vault door open, at last exposing the heart of the stronghold.  The room was filled with gold and jewels; the cat was tempted to take all of them, but she'd come here for one particular valuable target and figured taking anything else would be overkill.

And speak of the devil, there it was in a glass case in the middle of the room: a large transparent diamond, at least the size of a baseball.

Stretch-steppping up to the case, Blinkie produced a glass cutter from somewhere behind herself and applied it to the glass.  One quick circle later, the glass had a neat hole in it that she was able to reach the diamond through.

...Wait a minute.

There was one last security measure the cat had to take care of.  The diamond was on a weight-sensitive pedestal; just taking it off would set off an alarm.  She'd have to swap it for something else.

But what can I... aha!

Blinkie reached behind herself and peeled off the flattened guard that'd been stuck to her hindquarters the whole time.  Wadding him up into a ball, she reached him in, then with one smooth motion, replaced the diamond with him.  The security system was none the wiser.

The diamond she'd come to thieve now in her possession, Blinkie turned to leave... but before she did, she took out a note she'd written earlier and left it on top of the case, knowing the diamond's owner would find it the following morning.

Dear Baron von Buxx,
I guess it's sometimes true what they say about rich people being greedy jerks.  It's certainly true in your case, from what I've seen.  You do nothing with your wealth but hoard it and flaunt it, refusing to share it with anyone, while there are many others that would appreciate it a lot more than you do.
Since you won't do anything charitable with your money, I will.  I've taken the most valuable diamond in your collection; I'm going to sell it to the jewelry shop and donate the profit to charity.  Think of this as a message.
Signed, Blinkie