Possible Clues:

• Quality that keeps wallflowers by the wall
• Introvert’s attribute
• Hesitation to put launch onto loch
• Reserve hotel with counterfeit yen in three seconds
• Toss head showing lack of confidence
• What makes this posh boy in the class speechless at the back?
• Nervousness, timidity
• Introversion
• Timidity of head following fling
• Wallflower's quality