Ask her slaves to help her

"I have to plan stuff out," said Futaba. "If I leave all of a sudden, Sojiro will get suspicious. Okay, Kawakami, any ideas on how I can always be at your house every night?"

"Say you are going there for tutoring, Master Hypnotist Futaba," droned Kawakami.

"That's brilliant!" said Futaba. "I'll have to say it's for English or something. Sojiro knows I'm good at math and science. Now...Sumire, I know it'll be harder to plan around your gymnast schedule. Any ideas?"

"You don't need me every night, right, Master Hypnotist Futaba?" asked Sumire.

Futaba blinked. "Well, I guess not, once I have a good number of slaves...in fact, I could probably get a full itenerary planned out once I have my full harem. Mwehehe, imagine, Ann on Sundays, the Niijimas on Wednesdays, Haru on Fridays..."

She almost let her hand wander to her pants. "Ah, no! Focus, Futaba!" she hissed.