Automatically Execute Stored Procedure After Any RESTORE DATABASE Event
Does it have to execute immediately after the restore finishes, or can it be briefly delayed? One idea I had is to have a job that runs every minute, and checks for the Audit Backup/Restore Event in the default trace.

DECLARE @fn VARCHAR(MAX);

SELECT @fn = SUBSTRING([path], 0, LEN([path])-CHARINDEX(CHAR(92), REVERSE([path]))+1) 
  + CHAR(92) + 'Log.trc'  
FROM sys.traces   
WHERE is_default = 1;  

SELECT 
    DatabaseName,
    StartTime, 
    TextData
FROM sys.fn_trace_gettable(@fn, DEFAULT)  
WHERE EventClass = 115
AND TextData LIKE '%RESTORE%'; -- since can't differentiate between backup/restore


You could store the cleanups you've already done based on StartTime, and even limit the trace query that runs every minute (or whatever your acceptable delay threshold is) to only look at StartTime values greater than the last row you pulled, or the last time the job ran, whichever is less.