A quip BDSM gone wrong is a letdown (4,5)
I believe the answer is:
damp squib
'a letdown' is the definition.
I know nothing about this answer so I cannot tell whether it can be defined by this definition.
'a quip bdsm gone wrong' is the wordplay.
'gone wrong' indicates anagramming the letters.
'a'+'quip'+'bdsm'='aquipbdsm'
'aquipbdsm' anagrammed gives 'DAMP SQUIB'.
'is' is the link.
Can you help me to learn more?
(Other definitions for damp squib that I've seen before include "Something unsuccessful" , "It fizzles out" , "Firework that doesn't" , "Let-down" , "Unsuccessful attempt to impress, like moist firework" .)