It's already been established that this wasn't a good day for Harry, and it wasn't getting any better. When he woke up on the cold tiled kitchen floor after being punched by Dudley, he'd still been a little bit out of it. He'd hoped for a second to see Madame Pomfrey's face hovering over him, as had happened so often before. Instead, there was only Aunt Petunia, trying her best to cover any concern with a look of revulsion, and for the most part succeeding.
"Hurry, boy, we've got to get you fixed up before Aunt Marge gets here," she'd hissed, pulling him up by the arm and dragging him into the bathroom. She washed the blood off him and bandaged his wounds with her usual cold efficiency, barking instructions as she did so. "If anyone asks, it was one of the neighborhood boys who did this to you, and you deserved it. Not a word to anyone about my Dudders!" (Her voice was tinged with hysteria as she said the last part.) She yanked his arm again. "Do you understand, boy?"
Harry sighed in resignation. He'd learned long ago that it was easiest to go along with his aunt on everything. "Yes, Aunt Petunia." As she was leading him back to his cupboard, a thought tugged at his brain. "What was that you said about Aunt Marge?" he muttered groggily.
"She's coming for Dudley's birthday," Aunt Petunia said. "Not what I would have recommended when we've got two wizards in the house, but what can I do? She doesn't remember a thing about what happened last time she was here in your presence, so she shouldn't be overly suspicious. But I'm warning you, if you don't keep things reined in while she's here and get that Draco to do the same, who knows what will happen?"
She left then, and Harry collapsed onto his cot. He must have gone to sleep, because it seemed only a second later that Aunt Petunia was banging on his door again.
"Harry," she said in a panicky stage whisper, "Aunt Marge is here, and she wants to stay overnight! Go get your things out of Dudley's second bedroom and put them somewhere, anywhere, out of sight! And then move Draco's things to Dudley's first bedroom. They're going to have to room together until she leaves."
That at least gave Harry something to chuckle about as he pictured Draco's face when he heard this news. Somehow he didn't think Draco was going to be able to sleep at all that night. Instead, he'd probably be terrified of sharing a room with the "Muggle oaf."
Harry's mirth didn't last long, as he was soon faced with the conundrum of what to do with his things. Ordinarily he would have shoved them into the cupboard under the stairs, but for some reason that wouldn't work this time. He was strongly tempted to put a shrinking charm on everything and just put it on the top shelf of the closet, but then he remembered the letter from Malfalda Hopkirk and dismissed that as a bad idea. Finally he decided there was no choice but to lug everything down to the basement.
After that was accomplished and Draco's trunk was squashed into Dudley's room, it was almost time for supper. Draco and Dudley had just arrived home and were sitting uncomfortably in the living room with Aunt Marge, who was showing them a huge photograph album with pictures of all her dogs. (Fortunately for Harry, Ripper had died the year before and so was no longer Aunt Marge's traveling companion.) Harry sat down in a chair as far from Aunt Marge as he could and concentrated on looking interested and non-threatening.
It was working pretty well until Uncle Vernon came home. He was full of smiles and hugs for his sister, but couldn't resist bad-mouthing Harry all along, and of course she took the bait. Things were pretty tense by the time they sat down at the dinner table.
"Does the boy still go to St. Brutus', Vernon?" she asked peevishly.
"Yes, I'm afraid he does, Marge," Vernon replied. "When a boy's as twisted as our Harry here, there isn't much that can be done to cure him. Well, it says it right in the name of the school, doesn't it? 'Incurably Criminal boys.' There's really no hope for him at all, I'm afraid. He'll probably end up just like his parents."
Harry was trying his hardest to control himself, but it was quite difficult. Occlumency wouldn't work against Aunt Marge, unfortunately. Her evil was of the ordinary muggle sort. Even so, he was trying as hard as he could to stay calm and focused and not let her words get to him, but it was just barely working. The lights were flickering on and off, and the refrigerator was giving off a decidedly abnormal hum.
If Aunt Marge had remembered what happened last time she goaded Harry, she might have chosen her words more carefully. But a mind as small as hers tends to keep to familiar tracks, so she said pretty much the same thing she did the time before. "Well, I hope they aren't too soft on him at that school of his. I hope it's a thoroughly dreadful place."
A light bulb in the chandelier above the table suddenly popped. Everyone except Aunt Marge looked very frightened, and that made Harry glad. But then something happened that he'd never expected. Draco cleared his throat and spoke. "Oh, it really isn't that bad of a place. I should know. I happen to go there myself."