Become more involved with semi-empathic understanding (7)
I believe the answer is:
thicken
'become more involved' is the definition.
(e.g. a plot)
'semi-empathic understanding' is the wordplay.
I cannot quite understand how this works, but
'understanding' could be 'ken' (ken can mean someone's range of knowledge) and 'ken' is present in the answer.
This may be the basis of the clue (or it may be nonsense).
'with' is the link.
Can you help me to learn more?
(Other definitions for thicken that I've seen before include "Make dense" , "Become more viscous" , "Make less flowing" , "get fatter?" , "Clot" .)