Tortuously agonise with clue involving hours seated here? (6,6)
I believe the answer is:
chaise longue
'tortuously agonise with clue involving hours seated here?' is the definition.
Although both the answer and definition are singular nouns, I can't understand how they can define each other.
This is the entire clue.
Can you help me to learn more?
(Other definitions for chaise longue that I've seen before include "Type of sofa" , "Sofa for reclining on" , "Reclining seat with back and armrest" , "Partly backed couch with one arm" .)