Written for the D&D Harry Potter Challenge (Year 1) on HPFC, as well as the Prompt Relay Challenge (for the Humor genre).
This is exactly 300 words. And a quick disclaimer, underlined is a quote from OotP. The story is directly connected to those lines, so I had to include them.
"Don't you remember asking me, as you lay in the hospital wing, why Voldemort had tried to kill you when you were a baby?"
Harry nodded.
"The thing is, Harry," Dumbledore continued. "I have already told you why."
"I – I don't understand," said Harry, now more confused than he had been before.
"On the night your parents died, I did not immediately leave you at your aunt's doorstep. Instead, I brought you to my office to explain…"
"Harry," Dumbledore clasped his hands in front of him. "There is something very important I must speak to you about."
Harry gnawed at his blanket, encouraging Dumbledore to continue.
"You see, Harry," Dumbledore began, "I know no other way to say this. There is a prophecy about you and Lord Voldemort, the man who tried to kill you today."
Harry looked up, but did not stop chewing on the blanket. To show he understood, he kicked his legs out and swung them.
"Do you want to know what exactly it says?" Dumbledore asked.
"Nnngh," Harry said, squishing the blanket between chubby fists.
"Of course." Dumbledore sighed. "I'll keep it as simple as possible.
"The prophecy says that either you or Neville Longbottom may defeat Lord Voldemort. But I suspect that Voldemort has marked you as the one to defeat him. You, a halfblood like Voldemort, as opposed to Neville, a pureblood. The irony of this choice is something I find hilarious. Don't you?"
"Pphhhl," said Harry.
"Yes," Dumbledore said, nodding. "It is right to laugh. However, this is important. You have great responsibility. And if I suspect correctly…which I am prone to doing, mind you…then you may have to endanger yourself in order to defeat him. I am sorry, my boy."
Appropriately horrified, Harry fell asleep.