Maybe Rooney's drunk, snorting cocaine, right? (7)
I believe the answer is:
scouser
'maybe rooney's' is the definition.
I know nothing about this answer so I cannot tell whether it can be defined by this definition.
'drunk snorting cocaine right?' is the wordplay.
'drunk' becomes 'souse' (souse is a kind of drunk).
'snorting' means one lot of letters goes inside another (snort can mean to ingest through the nose).
'cocaine' becomes 'C' (drugs abbreviation).
'right?' becomes 'r' (common abbreviation).
'souse' enclosing 'c' is 'scouse'.
'scouse'+'r'='SCOUSER'
Can you help me to learn more?
(Other definitions for scouser that I've seen before include "one of the Beatles?" , "Northerner" , "Person from Liverpool" , "Bishop, perhaps" , "One from Liverpool" .)