There's some humanity in him no doubt (8)
I believe the answer is:
cannibal
'there's some humanity in him no doubt' is the definition.
The answer is a person as well as being a singular noun. This is suggested by the definition.
'there's some humanity in him no' is the wordplay.
I cannot really understand how this works, but
'there's' could be 'n' (I've seen this in other clues) and 'n' is present in the answer.
'some' could be 'a' and 'a' is present in the answer.
'him' could be 'al' and 'al' is located in the answer.
'no' could be 'n' (common abbreviation) and 'n' is located in the answer.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for cannibal that I've seen before include "Anthropophagite" , "Fellow consumer" , "Animal that eats its own kind" , "One eats human flesh" , "Person eating human flesh" .)