Lovers at it frenetically, increasingly under covers (8)
I believe the answer is:
amoretti
'lovers at' is the definition.
The definition suggests a singular noun which matches the answer.
'it frenetically increasingly under covers' is the wordplay.
'frenetically' indicates anagramming the letters (I've seen this in other clues).
'increasingly under' becomes 'amoret' (I can't explain this - if you can you should believe this answer much more).
'covers' says to put letters next to each other.
'it' anagrammed gives 'ti'.
'ti' put after 'amoret' is 'AMORETTI'.
Can you help me to learn more?
(Other definitions for amoretti that I've seen before include "Bonkers" , "images of Cupid" , "Plump lads" , "Pretty artistic boys" , "Little winged creatures" .)