Watch Walter fog up in the lingering warmth (9)
I believe the answer is:
afterglow
'the lingering warmth' is the definition.
The answer and definition can be both feelings as well as being singular nouns.
Perhaps there's a link between them I don't understand?
'watch walter fog up' is the wordplay.
'walter fog' can be anagrammed to 'AFTERGLOW'.
However, I am not clear how the anagram is indicated.
'in' is the link.
Can you help me to learn more?
(Other definitions for afterglow that I've seen before include "residual light" , "appearing when sun has set?" , "following which gloom sets in?" , "Light, lingering" , "Light in the sky post sunset" .)