Share some room together, having finished drink (7)
I believe the answer is:
overlap
'share some room together' is the definition.
'finished drink' is the wordplay.
'finished' becomes 'over' ('over' can be similar in meaning to 'finished').
'drink' becomes 'lap' (lapping is a kind of drinking**).
'over'+'lap'='OVERLAP'
'having' is the link.
(Other definitions for overlap that I've seen before include "Partially coincide" , "Common area of interest" , "Flap" , "Coincide in time or space" , "Extend over and cover a part of" .)