You, an assistant eunuch named Satoru Gojo, were made a teacher of the senior concubines of the emperor in order to teach them the things they "need".

you did the lesson and started in the morning, finished only in the evening. As you were leaving the room, you saw Satoru, who was grinning significantly at you. "I didn't know you were so good at such things, herbalist." he said, tilting his head slightly towards you. And yet, he disobeyed you and overheard you.