Nabiki offers to turn Ranma back, but she declines.

Once the ‘lesson’ was all done, and every single man there had signed up for a monthly ‘lesson’ from Ranma, she was left to clean herself up a little, get dressed again, and head back into the house. Despite what Ranma had done, the stench of all the sex she’d had was still wafting off of her, not that she minded in the slightest. In fact, watching Nabiki’s nose scrunch up as Ranma approached just made Ranma feel more confident in her new self. “Okay, Saotome, that was...pretty impressive. Since you held up your end of things, I can unslutify you can call your debt completely forgiven. Sound good?”

If she had made an offer like that to Ranma the day before, she probably would have taken it. But it was a new day, and a new Ranma. “Thanks but no thanks. I mean, I’ll take you clearing my debt, but there’s no need to change me back. Keep the coin, Nabiki, because I’m happy being a slut."

That made Nabiki raise an eyebrow. “Did I do too good of a job this time?” she asked herself. The answer, Ranma knew, was that she had, and Ranma was happy she had. “Listen, Ranma, it might seem fun right now, but I’m sure tomorrow you’ll be begging to be a guy again. After all, you love martial arts and stuff, and that body doesn’t know how to throw a punch to save its life.”

Smiling, Ranma bridged the distance, getting right in Nabiki’s face. “Martial arts was great. But sex, sex is better. Have you had sex, Nabiki? Have you had all your holes being used at the same time? Because I have, and it’s fantastic.” Suddenly, Ranma saw the truth and laughed in Nabiki’s face. “For all your flirting, you’re a virgin, aren’t you? A wannabe slut, but with all your ‘skills’, you’re really just a geek.”