Comic character in the end's beaten danger (6,3,6)
I believe the answer is:
dennis the menace
'comic character' is the definition.
(character in Beano comics)
'in the end's beaten danger' is the wordplay.
'beaten' is an anagram indicator (letters beaten up or destroyed).
'danger' becomes 'menace' (menace is a kind of danger).
'in'+'the'+'ends'='intheends'
'intheends' is an anagram of 'dennisthe'.
'dennisthe'+'menace'='DENNIS THE MENACE'
(Other definitions for dennis the menace that I've seen before include "As children's character" , "cartoon character" , "Young imp" , "Young tearaway" .)