Harry looks up from where he’s sitting on the swings to notice Dudley and his minions approaching. They’re laughing about something. Probably mugged a kid, or perhaps killed a puppy, Harry muses mentally. “Hey, Big D.”
The smirk on Dudley’s face pulls down into an angry scowl as he hears his cousin’s sarcastic greeting.
“Beat up another ten year old?” Harry asks conversationally.
“This one deserved it,” Dudley spits. His cronies let out a chorus of agreements behind him.
“Five against one. Very brave,” Harry comments.
“Well, you're one to talk!” Dudley says, stepping forward menacingly. “Moaning in your sleep every night? At least I'm not afraid of my pillow!”
“‘Don’t kill Cedric!’” Dudley mocks, repeating what Harry so often whimpers in his nightmares. “Who’s Cedric, your boyfriend?”
“Shut up,” Harry orders sharply, fighting to control his anger.
“‘He’s going to kill me, mum!’” Dudley continues jeering, ignoring the warning. Then he looks directly at his cousin. “Where is your mum? Where’s your mum, Potter?”
Harry’s blood is boiling. He didn't think even Dudley would sink this low. The bully himself looks a little shocked by his own words. “Don't talk about her. Or Cedric.”
Whatever hint of remorse Dudley might have shown is instantly wiped away. Harry’s words sets the gang off again, their laughter growing louder. “Is he actually your boyfriend, Potter?” Dudley crows.
“No,” Harry tells him. “He was my friend.”
Dudley looks faintly surprised at the use of the past tense- clearly he had assumed the dreams were fiction, and Cedric hadn't actually died. “Was?”
“Yes,” Harry snaps, “was. And I say that because he was killed in front of me. By the same guy who killed my parents, in fact.” He isn't sure why he's saying all this, but he supposes it doesn't really matter- Dudley’ll taunt him no matter what he says, and his friends will just think he's talking out of his arse.
As expected, the goons start laughing even harder. Dudley doesn't, though. He looks confused, and there’s something else there, too.
Harry shakes his head. “Just get away from me.” As he begins to walk away, the sky suddenly darkens. The wind picks up, and everything is coated in a menacing blue light.
The strange expression stays on Dudley’s face, even as his friends panic and scatter. “What are you doing?”
“I'm not doing anything!” Harry shouts, equally confused by the sudden change. Debris is starting to fly through the air, whipping around in the wind. He wonders briefly if it’s a tornado, but surely natural weather doesn't become disastrous so quickly.
The two begin to run, Harry in the lead as his huge cousin struggles to keep up. The dark clouds seem to be chasing them.
They manage to take shelter in an abandoned tunnel. Harry is filled with a sense of dread when he notices the lights flickering. Something is wrong.
Just as this occurs to him, a huge black figure swoops out of nowhere. Harry barely has time to recognize it as a Dementor before it’s pinning him to the wall by his throat. He struggles to catch his breath enough to choke out, “Dudley- run!”
After a slight hesitation, his cousin obeys, but within seconds his feet are swept out from under him by an invisible force. Another Dementor glides in, hovering over the trembling Muggle.
Harry struggles against the blackness that begins to cloud his vision as the Dementor starts its attack. He fights to overpower the screams of his parents, the vacant stare on Cedric’s face as he lay dead, the indescribable pain of the Cruciatus-
He manages to get his wand out and immediately hits the Dementor with it as hard as he can. It’s enough that the cloaked figure is jolted backwards and away from him, and that’s all he needs.
“Expecto patronum!” Harry cries, and immediately brilliant white light floods out of his wand and casts the Dementor away.
He turns to see that his cousin is still pinned down and turns his patronus around to fight his Dementor off as well.
Harry casts a wary eye over Dudley’s sweaty, trembling body, still lying on the dirty cement floor. This will be hard to explain to Aunt Petunia and Uncle Vernon…
Dudley is conscious, but too dazed to move.
With a sigh, Harry picks up Dudley’s feet and begins to walk, dragging his enormous cousin behind him. There’s no way he can carry him, so this is the best he can do.
After about half an hour of this method of transportation, Dudley finally comes to enough to snap that he can walk himself, and then proceed to lean heavily on Harry the whole way home.
“My little Duddykins!” Petunia shrieks when she sees them making their way up the driveway. She runs over and pulls her son into a hug, scowling at Harry over his shoulder.
“What's he done to you, sweetums?” She leads them inside, immediately getting Dudley a blanket and setting to work on making hot chocolate for him while cooing random words of comfort here and there.
Once Dudley has been properly fretted over, Petunia starts to ask about what happened.
Dudley, who is still in a mild state of shock, can't quite seem to find the words. He just throws random phrases together in no particular method or order. “Cloak… monsters… Harry… spell…”
“Harry cast a spell on you? He summoned monsters?!” Petunia cries in horror.
At that precise moment, Uncle Vernon walks in the front door, and Harry decides that if any type of god exists it must really want him dead.
“YOU WHAT?!” He roars, immediately turning a multitude of colors, ranging from vivid purple to the grey of week old porridge.
“I didn't-” Harry begins, but is cut off before he can get more than a few words out.
“WE TOOK YOU IN OUT OF THE GOODNESS OF OUR HEARTS AFTER YOUR WORTHLESS PARENTS GOT THEMSELVES KILLED, AND YOU GO AND DO THIS TO OUR PRECIOUS SON? YOU DISGRACE! YOU'LL BE OUT OF THIS HOUSE BEFORE MORNING!” Vernon bellows.
“How dare you!” Petunia picks up where Vernon left off, continuing to shriek at Harry. “I always knew you were a freak, but this is worse than I ever could have dreamed! We gave you our son’s clothes! We let you eat our food! How dare you be so ungrateful as to contaminate our household! How could you-”
“He saved me,” Dudley speaks up finally, his voice hollow and his expression still stunned.
“What?” Aunt Petunia gasps, clutching her chest.
“Did you mess with his mind?” Uncle Vernon roars, his face bright red as he looms over Harry’s small body. “Did you use that freakishness on my son? Answer me, boy!”
“No!” Harry cries. “I'm not allowed to use magic outside of school, remember?” He ignores the way his uncle flinches at ‘the m word’. “I'd be expelled!”
“Well, you summoned the- the monsters that attacked my Dudders! You were going to be expelled anyway, so you changed his memory of it!” Vernon concludes, rage about the magic and smugness over having figured out Harry’s master plan warring for dominance in his eyes.
“He was attacked too, Dad,” Dudley puts in hoarsely.
Vernon scoffs. “A likely story!”
“No, it's true!” Harry says desperately, overcoming his shock at Dudley’s support in order to defend himself. “It left bruises on my neck, see!” He tilts his head up so that the marks left from being choked are more visible.
Petunia appears somewhat unsure now, but Uncle Vernon just looks even angrier.
“You did that to yourself, no doubt!”
“What?!” Harry might have found the idiotic logic funny if he weren’t so scared.
“You're upsetting Duddykins!” Petunia frets.
“Just go to your room, boy,” Uncle Vernon growls. “We’ll finish this later.”
Harry doesn't need to be told twice. He jumps at the opportunity to escape the conversation and runs up the stairs, the sound of his aunt fussing over Dudley eventually fading when he closes his door.