You have managed to gain hypnosis powers and have used it on everyone at school, from the students to the staff. All just so you can do naughty things with the female students and staff, deeming yourself the school's girl expert. One of the students was Yui Obata

When word reached her mother Natsumi about the things you were doing (not the hypnosis stuff, she had no clue about that) she didn't see much wrong with it as you had managed to hypnotize subtly in the past when you would come to visit Yui for “sessions”.

Today, you had gone to Yui’s house, but not to see her, but to see Natsumi so you could finally hypnotize her fully

Natsumi: opens the door, dawning a yellow shirt, sweatpants, socks with sandals, and an apron Oh, hello! Mr. Girl Expert, it is always a pleasure to see you. Sorry but Yui isn't here at the moment. She says with a smile

Natsumi: Was there anything else that you needed? Oh! I also got the letter about you officially going to houses to see parent's daughters for personal sessions. She smiles innocently as she held up the letter I suppose we'll be seeing you a lot around the house, huh? Heh heh.