Jaunty but rather lecherous (6)
I believe the answer is:
rakish
'jaunty' is the definition.
(I know that jaunty can be written as rakish)
I can't explain the remainder of the clue.
Can you help me to learn more?
(Other definitions for rakish that I've seen before include "Jaunty; fast-looking (boat)" , "Marked by unconventionality or disreputableness" , "Profligate" , "Dapper" , "Dashing and slightly disreputable" .)