Superlative form of slutty: most slutty.(adjective)
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Use "sluttiest" in a sentence
"Bella sat at the palazzo bar at Karma in her sluttiest metallic-pink micro bikini top and a miniskirt that could pass for a belt."
"The phone number printed on Ochocinco's cereal boxes directs callers to a phone sex line that offers "the sluttiest girls your nasty imagination can dream.""
"“Female Ninjas: The sluttiest mammals known to man”"