Dappy is a cartoon charactor that always ends up dead. The cartoon is called "Dappy the Lappy". Try looking for it on Google or some other search engine. Dappy always fucks up and dies in a situation that he shouldn't have been in in the first place. Pulling a Dappy means getting hurt or die during a crime, or while you are doing something you wernt sposed to.
He pulled a dappy during a bank robbery, and got himself killed.