Device for listening in bed? (3)
I believe the answer is:
bug
'device' is the definition.
(bug is a kind of device)
I can't explain the remainder of the clue.
Can you help me to learn more?
(Other definitions for bug that I've seen before include "Small crawling creature, now in computer programs" , "Disease-germ" , "Tap" , "Harmful microorganism" , "Fault in program" .)