I agree with Alan

A "fluff piece" is a news story or report which is unimportant, and normally it is meant to be cute, funny, or something like that. For example, if a reporter does a story covering kittens, its probably a "fluff piece". The news agency chose that story not because it was important, but because it is cute and may help ratings.

A piece that can be taken out and the original statement would still hold true. Fluff in reference to English structure means extra.

What's the context? the situation?