On the catwalk, they're seldom upset (6)
I believe the answer is:
'on the catwalk' is the definition.
I can't judge whether this definition defines the answer.
'seldom upset' is the wordplay.
'upset' indicates an anagram.
'seldom' anagrammed gives 'MODELS'.
'they're' is the link.
Can you help me to learn more?
(Other definitions for models that I've seen before include "Seldom (anag)" , "Representative forms or patterns" , "Prototypes" , "Exemplars or mannequins" , "Poses for artists" .)