Make mawkish love, and so on, captivating Stephen's heart (5)
I believe the answer is:
spoon
'make mawkish love' is the definition.
Although both the answer and definition are singular nouns, I cannot see how one could define the other.
'so on captivating stephen's heart' is the wordplay.
'captivating' is an insertion indicator (captivate could historically mean to hold captive).
'heart' means to look at the middle letters.
The middle of 'stephen' is 'p'.
'so'+'on'='soon'
'soon' going around 'p' is 'SPOON'.
'and' acts as a link.
Can you help me to learn more?
(Other definitions for spoon that I've seen before include "A runcible item of cutlery?" , "One with bowl" , "Kiss - server" , "No knife" , "Dining utensil" .)