Boyfriend’s part of East End, according to report (4)
I believe the answer is:
beau
'boyfriend's' is the definition.
(synonyms)
'part of east end according to report' is the wordplay.
'part of east end' becomes 'Bow' (area of East London).
'according to report' indicates a 'sounds like' (homophone) clue.
'bow' sounds like 'BEAU'.
(Other definitions for beau that I've seen before include "Handsome man" , "One loving" , "An old-fashioned boy friend - like Brummel?" , "An old boy friend or dandy" , "Male admirer; dandy" .)