[x] Say nothing.
You swallow the urge to speak, your reason finally overcoming your excitement. No. It won't do to interrupt the girl so soon. (At least, you assume this person is a girl, from the ecstatic mention of some 'Harry Potter.') If left to her own devices, she might let slip a few details about the world outside that she otherwise wouldn't. After all, who's to say she'll trust a diary that answers back? A discerning wizard certainly wouldn't.
You hope, for your sake, that the girl is as young and naive as she sounds.
Untroubled by the disappearing ink, it seems, she continues to write.
Oh, well. They're all outside on their brooms for now, so they couldn't see it, even if it was there. I wish I could go play with them...Ron told me Harry's an absolute wonder in the air, and I'd so like to see it. But I just can't! I don't want to look all clammy and mute in front of him, especially if Fred and George start making fun of me. Which they will. It's really unbelievable that they're fourth years now. They act more like children than I do. I hate having so many brothers.
The mention of the twins 'casting' something before implied it, but the broomsticks are the final proof: you're definitely in the hands of a witch, not a Muggle. A blessing, to be sure, if anything about your current life could be said to be such. You close your eyes as this new wave of words washes over you, your mind working at a mile a minute to wrest any meaning from them.
The girl has at least three brothers: Ron, Fred, and George. They are likely older than her, going on her last sentence, and Fred and George are twins with a penchant for practical jokes and fraternal mischief. They are fourth years -- a possible reference to Hogwarts? The fact that this writing is in English makes it more likely, unless there's another English-speaking magic school that's sprung up during your imprisonment.
Ron knows Harry Potter, the boy that this girl is so infatuated with. He seems to possess a degree of fame, though why a celebrity would be staying with an average family is anybody's guess. Unless this family is also somehow famous? It's difficult to tell, from what little she's written. She didn't even have the decency to put a year to the day, which is apparently August 5th. Summer. Just a few weeks before school.
You feel the warm trickle of strength suddenly vanish, ripped out of you, leaving a cold, gnawing absence in its place. You open yours eyes once more. All the words above you have fallen and disappeared inside; now, meaningless scribbles of ink appear and disappear, crumbling into ash as they descend. She's stopped writing. The disappearing ink must have finally caught her attention.
Impressive that it took this long, really.
After a few moments of total blankness, slow words once float down to you.
Umm...why is my ink disappea
Another pause -- this one a bit longer -- and then a torrential downpour of pure black ink, a waterfall that fills your mouth and your eyes, foul and viscous and sticky. You'd drown, if there were lungs in your incorporeal excuse for a body, and despite your rational knowledge that you don't require air, you somehow try to gasp for breath in this acrid black sea.
A spill? A prank? An accident? What did you do, girl?
[ ] Speak
---[ ] Write-in (ten words max)
[ ] Remain silent