Good man joins other ranks backing ruler -- it's touching (8)

'touching' is the definition.
(stroking is a kind of touching)

'good man joins other ranks backing ruler' is the wordplay.
'good man' becomes 'st'.
'joins' says to put letters next to each other.
'other ranks' becomes 'or' (military abbreviation).
'backing' is a reversal indicator.
'ruler' becomes 'king' (king is a kind of ruler**).
'or' written backwards gives 'ro'.
'st'+'ro'+'king'='STROKING'

'it's' acts as a link.