Related Clues:

• Clark Kent-like
• Easily scared
• Averse to first moves
• Short at the poker table
• Like Piglet
• Wallflower-ish
• Slow to mix, say
• Alone on a Saturday night
• Not likely to make the first move
• Reluctant to meet people, say
• Start suddenly
• 'Once bitten, twice ___'
• Having no social engagement
• Far from fearless
• Reluctant to mix