Dobby the house elf was walking through an elf corridor late one night clutching something small tightly in his hand.
"Dobby is a very bad elf, Dobby has to punish himself for this." he kept saying as he walked, which echoed around the tunnel. He stopped in front of what seemed like a dead end, checked around him to make sure nobody was watching. Then he pushed at the the wall in front, which swung forward.
Dobby crawled out of the opening and onto a ledge. He was standing on top of the mantle piece in the Headmasters office. Dobby quietly shut the portrait that he had entered from behind, and climbed off.
"Dobby will be caught, Dobby will be in trouble." he whispered as he walked toward what looked like a bird bath. It was made of stone and had markings on the sides. The elf quietly pushed a chair over, looking around to make sure nobody was in there. The portraits lining the wall of Headmaster were all snoozing silently in their frames.
He positioned the chair beside what he knew to be a pensieve.
"Professor Dumbledore would be cross at Dobby if he knew Dobby was using his personal pensieve." he whispered.
The elf opened his hand reveal what he had been clutching, a tiny glass vile. With trembling fingers he uncorked it. As slowly as he dared, he held the vile above the pensive and started to tip the contents when a voice sounded behind him that made Dobby jump so violently that the bottle almost flew out of his hands. He reached out and caught it quickly and held it against his chest.
"Dobby?" Professor Dumbledore was standing behind him in a long dressing gown.
"Dobby is sorry sir!" squeaked the elf, "Dobby is leaving now sir."
"Nonsense." said Dumbledore, striding over to the pensive. "I see you know how to use a pensieve."
"Uh, yes sir, I is watching sir, I is learning sir."
"Do you mind me asking, what you were trying to watch?"
Dobby held out a trembling hand and showed the Professor the vile.
"It is a memory sir, the memory of when Harry Potter freed Dobby."
"Ah, do you mind if I join you?" he asked looking delighted.
"Oh, of course sir!" and he climbed back onto the chair and again, tipped the continence of the vile into the pensieve.
The memory swirled in the liquid and both Dobby and Dumbledore lowered their heads into the bowl. Dobby felt himself materialize in a Hogwarts corridor, Dumbledore beside him.
"Ah," said Dumbledore, looking around. "Seems like so long ago doesn't it?"
The silence of the castle was suddenly broken by loud quickly stifled screams. Dobby saw himself from three years ago turn a corner into view holding his head. Dobby scowled as a tall man with white blonde hair and black robes came into view behind him. The man, Lucius, had a cane and was hitting younger Dobby with it. Younger Dobby would shriek in pain as he was forced to walk in front of Lucius who hit him again and again.
"That really hurt." said present Dobby.
"I could imagine." said Dumbledore.
There were sounds of echoing footfalls drawing closer. Past Dobby stopped before a flight of stairs and closed his eyes, knowing he was going to be kicked down them, but the kick never came because Lucius' attention was interrupted by the sound of Harry Potters voice,
"Mr. Malfoy!" Harry Potter gasped stopping behind them, both Dobby and Lucius turned around to face him.
Harry Potter forced the old destroyed diary into Dobby's master's hand.
"What the-?" Lucius said in disgust.
Past Dobby could only see the bottom of the diary, him being only waist tall, but his master threw something black at Dobby and Dobby caught it.
Dumbledore looked at present Dobby who was smiling triumphantly. Past Dobby was examining the black thing and suddenly gasped when he learned that is was a sock, master had presented Dobby with clothes. Lucius was talking to Harry Potter, but Dobby wasn't listening.
"Come, Dobby. I said, come." Lucius snapped, but Dobby didn't move, Dobby didn't have to, for the first time ever, Dobby didn't have to.
Dobby held up the beautiful, the glorious, the slightly unsanitary sock, and was looking at it with admiration. Present Dobby was too.
"Master has given Dobby a sock," past Dobby said, "Master threw it to Dobby."
"What's that?" spat Lucius. "What did you say?"
"Got a sock. Master threw it, and Dobby caught it, and Dobby- Dobby is free."
Present Dobby and Dumbledore were both smiling at the look on Lucius' face.
"You've lost me my servant, boy!" said Malfoy, launching himself at Harry.
But past and present Dobby both shouted, "You shall not harm Harry Potter!"
There was a loud bang, and Malfoy was launched backward and down the stairs landing in a crumpled heap on the floor below.
"I had wanted to do that for a very long time sir." said present Dobby happily. "Oh! Oh watch!" he said pulling on Dumbledore's robes and pointing at his past self. Dumbledore looked around amused.
Lucius stood up red faced and pulled his wand out on Harry Potter, but past Dobby held up a finger threateningly and said, "You shall go. You shall not touch Harry Potter, you shall go now."
Lucius looked as though he wanted to kill both of them, but not having a choice, he hurried out of sight.
"Harry Potter freed Dobby!" past Dobby said excitedly. "Harry Potter set Dobby free!"
"Least I could do , Dobby," Harry said, smiling. "Just promise never to try to save my life again."
Past Dobby smiled, but present Dobby didn't.
"What's wrong, Dobby?" asked Dumbledore gazing down at him. "This is a happy memory."
"Dobby misses Harry Potter." he said.
"Aw," said Dumbledore, "You'll see him again, very soon I think too."
Dobby looked back up and smiled again.
"Harry Potter is greater than Dobby ever knew!" sobbed past Dobby. "Farewell, Harry Potter!" and with a loud crack, Dobby vanished.
The scene around them dissolved and they felt a flying sensation as they materialized back in Dumbledore's office again.
Dobby was grinning, his big orb eyes shining as he looked at Dumbledore, who stretched and said, "Well, that was refreshing. I really must be getting to bed though."
"Dobby thanks Dumbledore for his kindness!" Dobby squeaked.
"Ah, think nothing of it. Oh and Dobby, don't punish yourself for sneaking into my office, that's an order."
Dobby smiled and his eyes filled with tears and he walked from the room. Dumbledore waved his wand above the pensieve and the silver memory rose from the bowl and back into the vile,
"For a rainy day."