Tangle with men he’s upset (6)
I believe the answer is:
enmesh
'tangle' is the definition.
(enmeshing is a kind of tangling)
'with men he's upset' is the wordplay.
'with' means one lot of letters go next to another.
'upset' is an anagram indicator.
'men'+'hes' is 'menhes'.
'menhes' with letters rearranged gives 'ENMESH'.
(Other definitions for enmesh that I've seen before include "Entangle as in net" , "Entrap" , "To ensnare" , "Tangle up in a net" , "Involve, as in a net" .)