Crossword Genius

He'll fulfil his promise (3,2,3,4)

Ross

I believe the answer is:

man of his word

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'he'll' is the definition.
I don't know anything about this answer so I can't tell whether it can be defined by this definition.

'fulfil his promise' is the wordplay.
'fulfil' becomes 'manof' (I can't explain this - if you can you should believe this answer much more).
'promise' becomes 'word' (as in 'I give you my word').
'manof'+'his'+'word'='MAN OF HIS WORD'

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