Harry didn't actually care, though it would have been nicer if Draco had asked before taking some from Harry's bag, but still.... "Why does it matter, Dad?"
Snape was glowering by then, but it was Draco who answered.
"Because Dad here is just like you, Harry! He doesn't trust me an inch; actually went around spelling every parchment he could find so I couldn't cheat! Never mind that I used to cheat like mad and he knew it and never said a word. In fact he liked it then. Very Slytherin--"
"It's only Slytherin if you're not caught out at it," said Harry. "Otherwise it's just stupid."
"Figures you would think so," Draco shouted. "So I duplicated lines, so what? It's your fault anyway!"
"How is it my fault?" Harry shouted right back.
"I wasn't going to take your sodding parchment, I wasn't! I was going to start in on my lines for real!" Draco was screaming by then. From the look on Snape's face, Harry had a feeling his brother had been doing a lot of it. "But then you had to go and accuse me of going through your trunk, when it was Severus who went through it, looking for parchment! Well, if the two of you are going to both accuse me of sneakiness I figured I might as well get on with it! I wanted to work on sketching the crest, anyway!" With that, Draco yanked a few sheets of parchment from his pocket and brandished them like some sort of weapon.
Harry saw version after version of the crest done in black and white, some of them jerkily moving. Well, at least he knew what all the scratching noises had been.
"It's not my doing you like to cheat," Harry pointed out, though he did keep his voice to a normal pitch that time. "You just admitted that you used to cheat all the time."
"It is so your fault! You're a Gryffindor, so I thought you wouldn't like it much if I stole from you. And I wasn't going to! But since you already thought I had--"
"And why would I think a thing like that? Hmm, could it be because you did steal from me? As in, my invisibility cloak?"
"I borrowed it, Potter! Oh, sorry! Ten more points from--"
"Stop that at once," Snape finally said, standing up from his position at the table. "You know perfectly well you're not in charge of the counters."
"Well you are--"
"And you further know," Snape interrupted in a loud voice, "that I am not indulging your childish acrimony towards your House! Now, as for stealing, Draco, Harry and I had every reason to believe you would make free with his belongings when you felt the need was urgent! Do not use that to excuse your pitifully transparent attempt to evade your responsibilities!"
"Oh, like it was that big a deal--"
Harry couldn't believe his ears. Every trace of good feeling toward Draco--not to mention his resolve to keep his voice level--vanished straight away. "It was a big deal!" he yelled, stomping right over to where his brother was leaning against the wall. "It was a huge deal! You used my cloak to sneak out and got yourself accused of murder! You got expelled from school because you stole it! And then Dad took it away, because of you! And it was my father's!"
To Harry's horror, tears started to seep out the corners of his eyes, and he realised he wanted nothing better than to punch Draco straight in the face. Even though by then, Draco looked about as dreadful as Harry felt. Oh, maybe he just wanted to hit something. The wall...
Harry clenched both his fists into a tight balls.
"I meant the lines," Draco said in an undertone, shock written across every syllable. "Shite, Harry, the lines."
Whirling away, Harry gasped to get his breath back past the vice compressing his chest. He found himself colliding with Snape, who had moved to stand behind him. His father gathered him into a close hug, his hands moving up and down over Harry's back. "It's all right, Harry. Your father's cloak is safe and sound."
"Yeah, but you took it," Harry cried, the anger inside him just building and building until he felt like he'd fly apart from the pressure. Draco forgotten, Harry shoved against his father, hard, but Snape didn't let him go. "You take everything! I hardly have anything of his, and you took it all away! I thought you said you'd forgiven him!"
"Oh, Harry..." Snape's voice blew softly across the top of his hair. "It's only two things, you know, and I had good reason--"
"It's three things!" Harry tried to calm himself down, he really did, but the awful feelings inside him were still pouring out and he didn't know how to make them stop. He wanted them to; they hurt something awful. "You took my dad's mirror, too!"
The hands on his back had changed to patting him, now. "That was Black's, I thought?"
"No! Sirius gave me the one that used to be my father's!"
Draco spoke quietly behind him. "I'm sorry, Harry--"
Something about his brother's voice--that voice that had tossed so many insults his way in recent days--spiralled Harry's anger out of control. Snape's grip had eased off, so Harry yanked himself backwards and spun around, his clenched fist raised.
A voice inside of him was wailing, demanding he release his fury into a barrage of violence, but another part of him didn't want to hit his brother. And in trying not to, his anger came pouring out another way.
A gust of cold air suddenly swept through the room, a whooshing noise surrounding the three of them as something like a wraith rushed snakelike through the air. Draco's fringe flew up from the force of it, the manifestation coming closest to him, and then the thing, whatever it was, flew straight at the wall an inch from his head, hitting it with a noise like a thunderclap.
Draco leapt away, his mouth dropping open as he looked back at the granite wall, now coated in a fine layer of cracking ice.
"What the bloody hell was that?"
Well, at least the accidental magic had accomplished one thing. Harry didn't feel angry any longer; he just felt drained. "That was me, trying not to hit you."
"Oh..." Draco swallowed, one finger reaching out to poke at the icy wall.
"Perhaps you might consider before you next provoke your brother that he's prone to releasing dark powers when pushed hard enough," Snape warned. "You are unharmed?"
Draco actually looked himself over as though checking. "Yeah... it didn't hurt me, whatever it was."
"Harry?"
Harry felt shaken up, especially considering he'd thought his powers were under better control than that, but he nodded.
"Good." The Potions Master paused a moment, evidently weighing his options, for when he spoke it was to say, "Draco. I do believe I've been patient enough with your obstinacy. If you have now resorted to ferreting out unspelled parchments so that you may lie your way through your punishment, there is only one thing to do."
Snape held a hand out, palm facing upwards. "Return my grandfather's wand at once."
Now Draco was the one who looked shaken up. "I... I'm sorry, Severus. I don't know what's got into me, I really don't. I'll do your lines--"
"Yes, you will," said Snape, his voice as calm as the lake on a windless day. "What you won't do is magic. Any magic, until you're through your lines and caught up on your schoolwork. Now, return my grandfather's wand."
Draco slowly pulled it from his pocket and held it out, but Snape didn't take it. He waited until Draco reached out further and put it in his hand.
Snape wasted no time in tucking it away inside his robes.
Draco, Harry thought, looked like he might pass out. A dramatic reaction... an overreaction, in Harry's view, but then, Draco had always had magic, hadn't he? From his earliest memories, Lucius had let him start learning, ignoring the Ministry rules about underage magic. When his wand had been taken away before, he'd known that he had another.