D. All of the above.

Izuku cupped his chin, staring intently at Nomu. "...you know what? Let's go with all three," Izuku mused, rubbing his chin.

"Hmm? How will that work?" Ochaco asked as Momo gazed at Izuku, paying rapt attention to hear his thoughts.

"Well, given you suggested multiple personalities, Ochaco, that means we can also incorporate both mine and Momo's ideas into the final product," Izuku replied.

"Oh, so we're getting a bimbo after all? Sweet!" Momo giggled. "As long as it's not too boring for ya, Master~!" she winked.

Izuku chuckled sheepishly. "Those were Ochaco's words, not mine, though I don't fully disagree with the sentiment. Bimbos have their appeal, but they're a lot like junk food. Enjoyable on occasion, but you get sick of it if you have it constantly, so keeping a bimbo personality as just one side to her seems best."

"Alright then, so we got developing personality, and bimbo personality... What else?" Ochaco inquired, getting a little excited. There was an undeniable thrill to customizing a sister **** with Momo and their Master! Nomu was such a perfect blank slate, just waiting to become sentient, reborn into a life of carnal delight!

Izuku began muttering to himself rapidly, trying to determine what personas he would want to incorporate into the final product. He didn't want to add too many. "... let's go with a maid one, a nurse one, school girl with short term memory about any sexual knowledge, but always eager to relearn it, a total sex **** one, that one being as close to a genie mindset as possible, and a dominatrix one..."

"Dominatrix?" Momo blinked.

"I thought you didn't like submitting in bed, Master?" Ochaco asked curiously.

"That one's dominant side is not for me," Izuku answered simply.

"Oh, so she'll still be submissive to you, but mete out some disipline to us?" Momo perked up, really liking that particular idea. Ochaco seemed to agree, if her smile and blush was any indication.

"Exactly... And... Momo, can you grant her the ability to magically change her clothes based on the personality?" Izuku inquired.

"Easily!" Momo grinned enthusiatically.

"Oh, we're going to have to talk about giving me that power later!" Ochaco asserted.

"We will... now then, we'll have the developing persona form the base, with the other six being satellite personas... she'll automatically revert to her base self unless one personality is told to stick around longer after, let's say... an hour," Izuku nodded thoughtfully.

"Okay, and will you want each personality to be aware of each other?" Momo questioned, mentally taking notes as she casually pulled up Nomu's top and continuing to feel her up.

"...why not, so long as whatever mental conversations they have, they get along well enough, and aren't ever jealous of each other," Izuku decided. They spent the next ten minutes hashing out the details of each individual personality.