Oh, for once in his life, he wasn't going to be fate's butt-monkey. Back when he'd picked out his Army fatigues at Ethan's Costume Shop for his Halloween clothes and gone to the store counter to pay for this outfit, Xander had been absolutely startled when that weird English dude had taken his money, and then in turn handed to the boy a small card coated with a thin layer of material, just like a scratch-off lottery ticket.
The shopkeeper (Ethan somebody himself) had then courteously explained these cards were random prizes for his customers, with whatever these lucky people winning being hidden under- Xander hadn't bothered listening to anything else, as he eagerly scraped the ticket with his thumbnail, to soon reveal on the face of the card the odd words: "2 for 1". Looking up into Ethan's beaming face - a rather chilling smile there, to be sure - a dazed Xander heard from the older man that for his prize, the teenager now had the choice of keeping his earlier purchase, or he could chose from the entire shop any two other outfits, one for himself and one for anybody else the winner wanted to bestow upon with their second choice. Calling after a blur that had just headed deeper into the costume shop, Ethan had resignedly added the clearly-unheard proviso that these costumes had to fit their wearers; he wasn't going to alter anything.
Actually, Xander had been listening, even though he'd been moving at nearly the speed of sound. So, after shifting through the men's costumes, he'd picked his own choice, and then he went again throughout the store's costumes for kids and women in order to find something for Willow. Enough with the ghost costume, already! However, during his search, Xander found that absolutely special outfit, remembered what had happened in Buffy's bedroom a while back, and immediately knew that it was meant for nobody but Angel himself. Particularly, for whatever unfathomable reason, it was in that vampire's exact size.
The utterly incredulous look sent towards Xander by the proprietor when Ethan had seen the teenager lugging the pair of costumes towards the register counter had been more than enough to entertain the Sunnydale native, but it also caused Xander to totally miss how Ethan had worriedly eyed one outfit and then shifted his gaze to the other, only to then bemusedly shrug while the corners of the proprietor's mouth quirked in a quick flash of evil amusement.
Anyway, it'd all wound up with Xander on the park bench laughing until his ribs ached. The honest fact was, whatever his blonde friend's feelings were towards her childhood toy, Xander had no idea whatsoever how Buffy was going to react if Angel actually showed up on Halloween night wearing that unbelievable costume in real life. In any case, the most likely outcome was for Xander Harris to enter a whole world of hurt, as two angry people grimly tracked him down with their supernatural abilities, to then physically express their furious opinions about his glorious prank.
Still, it'd be totally worth it, if he did manage to pull this off.
Glancing at his wristwatch again, and seeing that he really did have to get to school, a smirking Xander stood up from the park bench, and after looking around himself to check that he was still alone there, this boy now struck a very familiar pose of someone about to soar upwards in his flight through a city's skies, all while chanting to himself the mantra for the Halloween character he'd chosen for himself, who in his own comic universe would be more than a match for any Slayer and vampire:
"Faster than a speeding bullet, more powerful than a locomotive, and able to leap tall buildings in a single bound!"