Dance affair (5)
I believe the answer is:
fling
This clue is a double definition.
'dance' is the first definition.
(I've seen this before)
'affair' is the second definition.
(a fling is a romantic affair)
(Other definitions for fling that I've seen before include "Vigorous Scottish dance" , "Brief relationship" , "good time" , "Brief affair; throw" , "Throw angrily in spell of indulgent pleasure" .)