Misanthrope showing a little mercy? Nice! (5)
I believe the answer is:
cynic
'misanthrope' is the definition.
(I've seen this before)
'a little mercy? nice' is the wordplay.
'a little' indicates a hidden word (a little bit of the clue).
'CYNIC' is hidden within 'mercy nice'.
'showing' acts as a link.
(Other definitions for cynic that I've seen before include "Someone who believes the worst of others" , "Misanthrope" , "One who thinks only self-interest motivates people" , "One believing the worst" , "Pessimistic viewer of human motives" .)