Clue: An upright and stylishly true character (6)
Answer: NATURE
Explanation: Definition: character
A charade of NA, a reversal ('upright' in a down light – but isn't 'upright' the right way up? I suppose that if one regards the natural posture of the word as horizontal, rendering it 'upright' could give the desired result) of 'an' plus TURE, an anagram ('stylishly') of 'true'.