2. A person who says something dirty or nasty or makes a comment with sexual overtones.
2. I told Lynsey that my legs hurt and she told me that I shouldn't keep them wrapped around my head so much. She is such a dirty bucket.
A dirty bucket is a sure-fire way to ensure drunkenness on a massive scale. A dirty bucket also has the potential to be dangerous, and so should be approached with caution.
Harry: "How about a dirty pint?"
Roger: "Sweet idea, but how are the rest of us going to get drunk?"
Harry: "Well, Roger, maybe we should make it a dirty bucket!"