Quickly eats starter of fish during unhurried retreat (5)

'quickly eats' is the definition.
'wolfs' can be an answer for 'eats' (to wolf something down is to eat it quickly). I'm not sure about the 'quickly' bit.

'starter of fish during unhurried retreat' is the wordplay.
'starter of' suggests taking the first letters.
'during' indicates putting letters inside.
'unhurried' becomes 'slow' (similar in meaning).
'retreat' shows that the letters should be reversed in order.
The initial letter of 'fish' is 'f'.
'f' inserted inside 'slow' is 'sflow'.
'sflow' in reverse letter order is 'WOLFS'.

Can you help me to learn more?