Took a seat with a nice short black (7)
I believe the answer is:
satanic
'black' is the definition.
(thesaurus)
'took a seat with a nice short' is the wordplay.
'took a seat' becomes 'sat' (I've seen this before).
'with' says to put letters next to each other.
'short' means to remove the last letter.
'nice' with its last letter taken off is 'nic'.
'sat'+'a'+'nic'='SATANIC'
(Other definitions for satanic that I've seen before include "Like hell it is" , "Diabolical" , "Nick's" , "like Mephisto" , "Bad" .)