Nasty person, but with a beautiful skin (5)
I believe the answer is:
snake
'nasty person' is the definition.
'snake' can be an answer for 'person' (snake is a kind of person). I'm not sure about the 'nasty' bit.
I cannot understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for snake that I've seen before include "Entertainer with music and reptiles" , "Long slender reptile" , "Part of plant or hair" , "former EC currency band" , "Chinese zodiac animal" .)