Does he always hurt the one he loves? (6)
I believe the answer is:
sadist
'one he loves?' is the definition.
The answer is a person as well as being a singular noun. This is suggested by the definition.
'does he always hurt the' is the wordplay.
I cannot quite understand how this works, but
'he' could be 'ad' and 'ad' is found in the answer.
'the' could be 't' (the is pronounced as a 't' sound in some dialects) and 't' is found within the answer.
The remaining letters 'sis' is a valid word which might be clued in a way I don't see.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for sadist that I've seen before include "Person who likes to inflict pain" , "It's sad to find person who enjoys hurting others" , "Tormentor" , "Savage'!?" , "One who loves being cruel" .)