As far as I am aware there is no such molecule. Opioids, like many ligands, bind receptors in a dynamic equilibrium meaning they are constantly binding and dissociating. Some are 'stickier' than others but none of them require enzymatic removal. The life cycle of the drug starts with high concentrations in your blood soon after taking it. It then diffuses down its concentration gradient into various tissues including the CNS where it binds mu opioid receptors to create an analgesic effect. As the liver removes it from the blood, the concentration gradient gets reversed with higher concentrations in the tissues and lower in the blood. So it once again diffuses down the concentration gradient back into the blood system where it gets removed.

Receptors may get endocytosed by neurons to prevent continued activation, but this doesn't necessarily remove the opioid from the receptor, it just prevents downstream signaling.

Dissociation of opioids from receptors (computation modeling)

https://pubs.acs.org/doi/10.1021/jacsau.1c00341

Endocytosis of opioid receptors after activation

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3683597/