School is where the girls are.

John didn't have to think about it long. "I'm still going to go to school. I can just give myself all the answers sure but I'm not going to get a girlfriend just sitting around here."
"No of course not. What was I thinking."
"Hey, why not do that?" Melanie asked "Make the three of us super smart and turn the school into our personal harem."
John looked at his sister a moment. The changes must have been having side effects. There was no way she'd have suggested that before. Then again she'd ever had reason to even consider it an option before.
"Ok. Good idea." John smiled before closing her eyes. She made herself and her sisters super geniuses each masters in their chosen topic to the point no one would even come near their level. She transferred everyone under age or too old out of the school before turning the school into the Doe family harem which she divided it into three groups. One for the people interested in herself, one for people interested in Erica, and one for people interested in Melanie. She also made it that no one she or her sisters wouldn't also be interested in was in any of the groups. And to hell with it, John may not have known what her sisters were into but she could still make sure that would be in the harem. Just make it that the Doe family harem had a power so those who got in would transform slowly over time to become one of their master's fantasies and people who share that fantasy would be more likely to get in and would consequently become a more **** version of the fantasy. There, Now John wouldn't even need to change anything herself while she was there enjoying herself. "So shall we go to 'school' then?"
"Yes I think we shall." Melanie laughed back.
Outside, they found that Erica had been having fun herself. She was now naked and receiving a belly rub. She looked over at her sisters. "You made some more changes."
"Yeah I did." John nodded. "And you've been testing the limits of what you can get away with."
"I gave up on that." Erica yawned. "I think the limit you created is beyond what I'm willing to do. No one even reacted when I went to the toilet in front of them."
Melanie screwed up her face "Ew you did that?"
"Well she is a cat girl and this is all normal cat-girl behaviour." John shrugged.
"And what's normal behaviour for a futanari?" Melanie sneered.
"According to the internet it's masturbating continuously and fucking anything with a hole in it but I'm a more reserved futanari."
Erica rolled back onto her feet and pounced over to beside her sisters. "You disapprove now Melanie but pretty soon you'll be doing things with those hyper melons that." She purred.
"Speaking of that, lets go make use of our harem already." John Grinned.
The building that used to be a school was still the same shape but there was no thinking that this surgically clean funhouse ever wasn't the Doe family harem. According to everyone else's memory it was built generations ago as somewhere for the men of the family to keep their wives. During the women's revolution the wives took it over and then some of them filled the place with men. These days it's for either side of the family the men or the women. Which, in the town, was only the three sisters.
Erica wen inside first followed by John and then Melanie.