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2.
Someone who is devious, cheeky and very naughty. Because of these almost superhuman levels of deviousness, the actions of a 'slippery customer' cannot be easily controlled. Such characters can cause complete carnage in many different situations (any day of the week). A 'Slippery Customer' is certainly not a valued member of society. In some cultures, using such a term to describe someone is the deepest form of insult.
Who is that sneaking off into the cafe toilets?

I'm not sure, but i've heard he's a seriously Slippery Customer.

People like him have certainly derailed from the road to glory...
by MarcusHasMassiveTekkers February 14, 2011
 
1.
Someone who is devious, cheeky and very naughty.

Because of these almost superhuman levels of deviousness, the actions of a 'slippery customer' cannot be easily controlled. Such characters can cause complete carnage in many different situations (any day of the week).

A 'Slippery Customer' is certainly not a valued member of society. In some cultures, using such a term to describe someone is the deepest form of insult.
Who is that sneaking off into the cafe toilets?

I'm not sure, but i've heard he's a seriously Slippery Customer.
by MarcusHasMassiveTekkers February 20, 2011