Possible Clues:

• 'Well, looky who just came in!'
• 'Here he is now!'
• “And here he is now!”
• Welcome subject of discussion
• Nick�s missus has climax frequently, it�s said -- and guess who�s here!
• Reaction to a coincidental entrance
• "Greeting" clued by the first parts of 16-, 20-, 56- and 65-Across
• ''Mention you and there you are!''
• The very one, she'd accepted climax frequently sinful
• Bishop's advice to a priest preparing a sermon on sins?