Possible Clues:

• Filth, look, seen in most of plaza
• Most of team learning endless filth
• Disgusting filth
• Sordid, neglected state
• Old-fashioned look adopted by traditionalist reduced sleaze
• Dirtiness
• Verdi's Egyptian opera
• Poverty? Blow's reduced when given gold
• Dirty and unpleasant state (in which to live)
• Peer's heading off men after Sun's beginning to reveal sleaze