I would slowly begin looting their house of items of increasing importance and value. Like, first a pencil, a paperweight, maybe some small foodstuffs, and work my way up to something like a cat. But I'd give them back if they ever admitted they stole my shit.- Windy

I'd steal something of theirs, fill it with dog crap and replace it where I took it from. I'd never tell them I did it but I'd give them a pooper scooper as a gift.- LittleJohn

Keep the gift and shut up about it. I got my stuff back...... Keep this person at a distance in the future.- Bella

i would donkey punch them for lying to my face- waldo

I'd be upset with that person, but might forgive him/her eventually- reddfrogg

I'd poke their jaja and call it a day. - buttface

I'd pump a load down their windpipe- Cessna

Kind of like our taxes and G W B's brilliant economic stimulus check plan? What a farce! - little member

hmmmmmmmm.... kick them in the balls or puch the shit ass junkie in the head abd then get a lock for my door, only to continue to puch the fuck in the head every time i saw him for ohh let's say for the next year or two.- ergott

I'd rip their head off, pump a load of man gravy down their windpipe, and re-attach their head backwards. Then I would insist that I didn't do it while I was zipping up my pants.- Cessna

I'd laugh. And then kick said person in the crotch.- Mel

ohhh...they gave it back- sanju

I would punch them in the face.- NIKKI

I would act very excited when they gave it back to me, saying that I've always wanted one, and where on Earth did they find it?! Then I'd give it back to them after the incident had been forgotten, after the suitable amount of wear and tear had been accumulated. I would also make sure that the cum stains were apparent, while asserting how expensive it was. Then I'd steal the bastard's wallet and buy a new one. - BlatantlyIgnorant

I think beating them to death witht he item is not an overreaction.- Dirty Dingus McGee

all is fair in love in war, they would get the same treatment right back at them.- vin

I would forgive- danandmei

Double personality- MCR

I would tie them to a chair and perform all the things I listed in my previous answer. Or...oh!...even better, challenge them to a Guitar Hero guitar-off and watch as they scream and cry as they hear their tendons and fingers snap and break while attempting to play Dragon Force's "Through the Fire & Flames" for the 10th time in a row.- McDiablo

I would do the same thing to them, only twice and keep something for myself.- Co3

I would play thier game but take it up a notch. If they want to play stupid I will too, but with their dog. I would make sure the last time they saw rover was with me, then I would kidnapp the mutt and when they asked me about it I would tell them I have no idea were they dog went and give them a big speech on how to be more responsible with their dog and should have been more careful. Then I would begin the slow process of giving the dog back. Everymoring I would leave a leg or a rib or a tail until I gave him the head and he would have his dog back but in peices. All the while sarcastically claiming my innocence. That should teach him to mess with my stuff and then play stupid about it - If I only had a navel....