A virtual fool, thirty, dressed up as children's character (5,5)
I believe the answer is:
tooth fairy
'a virtual fool thirty dressed up as children's' is the definition.
I know nothing about this answer so I can't judge whether it can be defined by this definition.
'character' is the wordplay.
I cannot quite understand how this works, but
'character' could be 'air' (air can mean a character or mood) and 'air' is found within the answer.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for tooth fairy that I've seen before include "It may bring comfort to a child" , "She leaves money for molar" , "Parent really" , "Spirit said to leave money at night in compensation for losing a gnasher" , "Visitor leaving kids money" .)