Amorous behaviour not unknown in secluded little spot (4)
I believe the answer is:
nook
'secluded little spot' is the definition.
I don't understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for nook that I've seen before include "Quiet corner" , "shady retreat" , "Cubbyhole" , "Alcove" , "Secluded corner" .)