One getting back around half five seeing red (7)
I believe the answer is:
avenger
'one getting back' is the definition.
(someone who gets back at others)
'around half five seeing red' is the wordplay.
'around' indicates putting letters inside.
'half' means to take half the letters.
'seeing red' becomes 'anger' (seeing red is getting angry).
'five' cut in half is 've'.
've' put into 'anger' is 'AVENGER'.
(Other definitions for avenger that I've seen before include "Bringer of retribution" , "One wanting retribution" , "One who retaliates -- engrave (anag)" , "One bent on retaliation." , "One exacts retribution" .)