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Now suppose we have a functor $\mathcal{C} \xrightarrow{F} \mathcal{D}$. The identity profunctor on $\mathcal{D}$ is given by the Hom-functor $\mathcal{D}(-, =)$. Now $F$ embeds contravariantly as a profunctor from $\mathcal{D} \to \mathcal{C}$, by a left action on this Hom, i.e. it maps $(c, d) \mapsto \mathcal{D}(F c, d)$, and covariantly as a profunctor $\mathcal{C} \to \mathcal{D}$ by a right action similarly. These are denoted $F_*$ and $F^*$ respectively, and also have an adjointness relationship $F^* \dashv F_*$ . These profunctors are particularly important, and are called the (co)representable profunctors - morally, every profunctor is the same as some functor precisely when it is representable.

Is there some relationship between these two mappings, or is the connection merely superficial?

F. Borceux, *Handbook of categorical algebra*. Cambridge ; New York: Cambridge University Press, 1994.