...A bag... Looking into the bag there's a device that looks kinda like a gun and a small booklet. Calling the booklet a booklet may have been a little bit generous considering inside were the words "point and shoot. Inanimate objects and plants may or may not gain some amount of sentience." followed with what looked like a rough drawing of the gun and an arrow pointing to a chamber which read "Refill with magic here."
It didn't cost much so you took it to the counter where you asked "So... any idea what this is?"
The clerk took a look at it and said "Some sorta magic gun that... does something to whatever you shoot at... and it doesn't have it's own magic generator so you've got to supply it with magic somehow... although it looks like it has enough for a few shots..." then the clerk looked around at the empty shop and then asked "...I can go get a book on what we've got in the discounted bin?" You nodded and then the clerk looked particularly annoyed. After a few minutes the clerk came back and said "Lets see let's see... Ok... Probably not the teleport gun that doesn't teleport itself... that had an internal charger... Probably not... no... Ah... I think this may be a match!"
"What is it?" you pondered
"The Girlfriend Gun! The intent was that you shoot a target and then it becomes your girlfriend, and then after some sorta condition the target reverts."
You remembered the booklet and parroted "and plants or inanimates may gain sentience..."
The clerk shrugged "It was in the discount bin for a reason. The book here says that there were a couple different models but the item just didn't really work out to continue producing. Can't really haggle the price of the discount bin, but you could consider whatever's left in the chamber to be a trial period."
You put the money down and said "Well... I guess I'll try it..." As you walked home you thought about how you'd use it. There seemed like there were a few more switches but not knowing what exactly this thing did you decided not to try fiddling with it yet. However as far as you knew the gun would give you a girlfriend... temporarily. The question was what would you shoot, and what exactly was this gun?