Style of fellow, loveless emperor (6)
I believe the answer is:
manner
'style' is the definition.
(I know that style can be written as manner)
'fellow loveless emperor' is the wordplay.
'fellow' becomes 'man' (fellow can mean a man).
'loveless emperor' becomes 'ner' (I can't justify this - if you can you should give a lot more credence to this answer).
'man'+'ner'='MANNER'
'of' acts as a link.
(Other definitions for manner that I've seen before include "Way or means" , "Kind, sort" , "Demeanour" , "Bearing; style of art" , "Mode" .)