fluff vs mess up

fluff is a noun but mess up is not a noun.

Word	Noun	Adjective	Verb	Adverb
fluff	Yes	No	Yes	No
mess up	No	No	Yes	No

As verbs, fluff and mess up are synonyms defined as:

fluff (noun)	mess up (noun)
a blunder (especially an actor's forgetting the lines)
something of little value or significance
any light downy material

fluff (verb)	mess up (verb)
ruffle (one's hair) by combing the ends towards the scalp, for a full effect	make a mess of or create disorder in
erect or fluff up	disturb the smoothness of
make a mess of, destroy or ruin	make a mess of, destroy or ruin