A mischievous little scamp and his antics (6)
I believe the answer is:
impish
'a mischievous' is the definition.
(I know that mischievous can be written as impish)
'little scamp and his antics' is the wordplay.
I cannot really see how this works, but
'scamp' could be 'imp' (synonyms) and 'imp' is located in the answer.
an anagram of 'his' is 'ish' which is within the answer.
No letters remain.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for impish that I've seen before include "Mischievous like small devil" , "Playful" , "Mischievous like small fairy" , "Wicked" , "Naughty" .)