I’ll bet you’re pouting. Because you think it’s safe now. The presents are already unwrapped and already broken or mentally returned to wherever they were bought and thus placed somewhere safe so no one will spill eggnog or figgy pudding* on them, thus rendering them unreturnable, because, really, even Frederick’s of Hollywood has its standards and kinda frowns upon egg, nog, fig, ‘n’ pud stains. Or, if not already unwrapped, then waiting under the tree for you to pounce upon them and discover that, really, no one paid any attention to your list, and oh my god, is your mother that deaf that she misheard you when you said “X Box” and now what the hell are you going to do with a box of Ex-Lax.
So you’re pouting. You think you’re safe from the wrath of the bulbous bastard in the red suit. (That’d be Santa, not Satan. Satan’s hardly bulbous. He stays very slim in the high heat of Hades.) You think, Well, the presents are already here, and Santa is not gonna be a dick and plunk his enormous, jingle-jangly ass back down the chimney, barrel his way over to the presents, scoop them up in his arms and into his big big bag, and then storm out the front door (he looks ridiculous trying to wedge himself back up the chimney, and the effect he’s going for surely would be lost), where he’ll stomp on them with his huge black boots and break everything beyond recognition, until left in the non-snow of your front yard is an immense mass of broken dreams.
That’s what you think. And you are wrong. Not only will Santa do all the things you think he won’t, but he’ll throw extra evil into the mix. Before he trashes the gifts you’ve unearned by dint of your pout, he will dash around the house and spike the eggnog with something entirely non-festive, spit in the figgy pudding, make out with your mom (in front of Dad!), and eat all the cookies your little brother Jimmy left on a plate last night on the mantel. And he’ll choke on them and tell Jimmy, directly to his face, that the cookies taste like something Prancer scraped off his hoof.
So stop pouting. Santa’s still in town, and he’s not above taking back what he’s given you.

* Yes, this is the third time in three days that I’ve mentioned figgy pudding. You are very observant!