Host now joins that woman, topless (9)
I believe the answer is:
presenter
'host now joins that woman topless' is the definition.
'presenter' can be an answer for 'host' (e.g. for a television show). I'm unsure of the remainder of the definition.
'host now joins' is the wordplay.
'host' becomes 'er' (I can't explain this - if you can you should believe this answer much more).
'now' becomes 'present' (the present time).
'joins' says to put letters next to each other.
'er' after 'present' is 'PRESENTER'.
Can you help me to learn more?
(Other definitions for presenter that I've seen before include "Radio/TV personality" , "Disc jockey" , "anchor?" , "TV introducer" , "Compere" .)