A little scary — a tidy figure going to support building, perhaps (8)
I believe the answer is:
caryatid
'figure going to support building perhaps' is the definition.
(type of sculpture used as a pillar)
'a little scary a tidy' is the wordplay.
'a little' indicates the answer is hidden within the clue.
'CARYATID' is hidden within 'scary a tidy'.
(Other definitions for caryatid that I've seen before include "Column in shape of woman" , "supporting woman that's stony" , "She gives support in her column" , "Sculptured female figure as support pillar" , "Column in female form" .)