The ml could have just expel nobel lady On for infidelity and disloyalty to the emperor he's so stupid.
That'd be pretty hard to do since he's been sending a body double to the concubines. You can't just accuse a concubine of high standing of infidelity like that when as far as everyone knows the emperor's been sleeping with the concubines regularly.
The ml could have just expel nobel lady On for infidelity and disloyalty to the emperor he's so stupid.