As interesting as a magical pen sounds, you're a typical teenage guy—there was never any doubt that you'd settle on the 'lust powder.' Thus decided, you grab the vial and walk up to the front of the store, where the elderly proprietor is hanging a freshly-painted sign over the counter. After he hammers the last nail into place, he turns to you and smiles, gesturing elaborately at the elegant lettering which reads: 'Because I am a wizard.'
"So," he beams, "what do you think?"
You search frantically for a tactful reply. What to say to a grown man in a bathrobe claiming to be a wizard? You've suspected since you first saw his robe that this guy might be more than a little senile—if not actively insane—but you hardly want to say that, especially if it's true.
"It's… nice," you say.
"I most certainly am not!" huffs the old man.
"You're not nice?" you ask nervously.
"What? No, I'm not senile."
You take a step back. "How did you know—"
With a flourish, the old man points to the still-wet sign.
"Um… right," you say.
"Oh, I know you don't yet believe—that doesn't matter. I only mentioned it because you asked. Well, that and perhaps a little excitement with the new sign—but mostly because you asked. I used to have a rather nice one, you know, with embossed gold lettering and all that. I was really quite fond of it. Quite an unfortunate affair what happened. There were these luchadores, and—ah, well, never mind. It's a rather long story and I'm sure you have places to go. Now, what can I help you with?"
Luchadores? As in masked Mexican wrestlers? Whatever—the man's probably crazy anyway. Better to make your purchase and get out.
"So, uh, how much for this powder?" you ask, nervously producing it.
"Ah!" he says. "Lust Powder! That's a very powerful substance, young man. I trust you read the label?
You nod.
"Then you realize that this powder will make you irresistible to your target? And that it doesn't wear off?"
"Yeah, I guess," you say, blushing. It sounds even sillier out loud.
The old man looks at you appraisingly. Finally, he nods.
"Very well," he says. "You may have the powder for sixteen dollars and seventy-three cents."
Emptying your pocket, you are surprised to find that you have exactly that amount.
"That's weird, how did you know—"
Once again, the old man simply sighs wearily and points to the sign.
"Oh. Right."
Handing him the money, you pocket the vial and walk hurriedly out of the store.
Once back out in the food court, you idly flip the vial over in your hand. Who to use it on? The vial only seemed to contain enough powder for once dose, so you'd have to choose carefully. You could use it here at the mall—there were plenty of girls here you wouldn't mind throwing themselves at you. You didn't really know any of them personally, though—maybe you should take the powder to school and use it on someone there. On the other hand, this wasn't a decision to be taken lightly—whoever you touched with it would apparently be attracted to you for life. Maybe you should wait until a particularly special opportunity comes along.