Possible Clues:

• Edges furtively
• Sneaks doing nothing aboard ship
• Son does nothing, but edges along warily
• Moves with one's back against a wall, say
• Moves edgewise
• Move sideways or furtively
• Creeps like a crab
• Moves like a crab --> Slaw and fries, for two
• Moves sideways or furtively
• Walks sideways like crab