He wanted to catch Dumbledore’s eye, but Dumbledore was not looking his way; he was continuing to look up at the obviously flustered Fudge.
’— FILTHY HALF-BREEDS, BESMIRCHING THE HOUSE OF MY FATHERS —’ Hermione came hurrying into the room looking flustered, just as Harry was putting on his trainers.
Hermione jumped up, looking flustered.
Oh — oh, right,’ said Ron, very flustered.
His greatest weakness was a tendency to lose confidence after he’d made a blunder; if he let in one goal he became flustered and was therefore likely to miss more.
"’It is with great regret that I must confirm that the wizard styling himself Lord — well, you know who I mean — is alive and among us again," said Fudge, looking tired and flustered as he addressed reporters.
Well… anyway…" said Hagrid, turning back to the class and looking slightly flustered, ’erm… what was I sayin’?
There are no more uses of "fluster" in the book.
Show samples from other sources
He gets flustered when talking to groups and tends to lose his train of thought.