Responses
I could be so wrong but is it Your Majesty Is Mine? I read this ages ago so idk if i'm remembering this right but i'm pretty sure she got isekaid and teaches him some stuff LMAOO. so sorry for getting your hopes up if its not...
Basically there is a women who gets isekaid and go to old times. She is in the harem of emperor. And quickly become fav women of harem and all others are jealous.
She advises the emperor and teaches him love making