Possible Clues:

• Be relatively unobservant, and totally innocent
• As you see, not so clean
• Be like one relatively inattentive and innocent
• Above reproach - perfectly clean
• Very clean location? Not so
• Don't see so much of what's so clean
• Don't see so much if you want to keep it clean
• Pristine
• Perfect start in snooker, then unable to sink a ball?
• Clean me out if the south leaves me penniless