Comparative form of filthy: more filthy(adjective)
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Use "filthier" in a sentence
"Katie Price AKA Jordan is "filthier" in bed when she's sober."
"Katie Price is "filthier" in bed when she's sober."
"Oh and show me just how mature you all are by calling me more names, filthier ones please, the last spate of sophomoric abuse was too lame to even consider insulting."