I got three whores with me, it smells like Dior and derrière
Christian Dior is a french designer that makes fragrances and makeup. Derrière is french for ass. It means that Kendrick has been spending time with the ladies.
There might be some number wordplay in this line and the previous one. He counts down from c4, to three hoes, to Dior (di- is a prefix meaning two). The counting down could also relate to an explosion, which would fit in with the theme Lamar has cultivated via his lyrics thus far.
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