"Oh, I…I'm sorry, M…Malfoy. I d…didn't see you," Longbottom stuttered.
Draco's eye twitched. "Yes, you are very sorry, aren't you. I bet Mrs. Longbottom is ashamed she has such a worthless nothing as a grandson. After this year, I'm sure she'll pull you out once she realizes what a pathetic waste of money, space and oxygen you are."
Longbottom sniffed.
"I bet she's wishing, right now, that it was you that had been Crucio'd into insanity rather than your parents, not that they didn't deserve it, worthless little blood traitors that they are." Draco knew that normally he wouldn't take his teasing this far, and felt a slight twinge of guilt. Any chance that Longbottom had of being graced with one of his rare, valuable and very sought after apologies were washed down the drain the moment Longbottom drew his wand.
He waved it threatening. "Don't. Talk. About. My Parents. That. Way!" He said in between sniffs. He waved his wand, and attempted the Levitation charm. Instead a suit of armor was smashed in.
"Locomortor Mortis," Draco said, contemptuously. After seeing Longbottom wobble for a few minutes, begin to cry a bit, and start hopping up to Gryffindor Tower, Draco finally left feeling generally unstressed and ready to face the world.