Extremely drunk, bishop on top of house (6)
I believe the answer is:
blotto
'extremely drunk' is the definition.
(I've seen this before)
'bishop on top of house' is the wordplay.
'on top of' indicates taking the first letters (I've seen 'on top' mean this).
'house' becomes 'lotto' (I've seen this before).
The initial letter of 'bishop' is 'b'.
'b'+'lotto'='BLOTTO'
(Other definitions for blotto that I've seen before include "Extremely drunk" , "Dead drunk" , "under the table" , "Helplessly drunk (slang)" , "Smashed" .)