Swear to him that she will never do it again

"I need you to promise me that you will never beg a male teacher to look at your bare crotch again," Mr. Dinger said.

Amethyst blinked, "Wait, that's it? That's easy: I promise to never do it again."

To her surprise, the teacher shook his head with a frown, "See, this is the issue I'm having with all the promises you've made to me so far. The way you're saying it, I can't tell if you're being sincere or not."

"What the hell are you talking about?" Amethyst said, "I'm the most sincere person at this school!"

"Maybe, but you aren't making promises like you are," he replied, "After all, isn't it true that if a woman is promising something, she swears it on her vagina, with the sincerity of the promise being directly correlated with the level of vulgarity that she uses to describe it?"

"Y-Yes, that's true..." Amethyst said, already starting to see the problem.

"So if you really were the most sincere woman at this school, you would be swearing on it in a way that would make sailors blush, wouldn't you?"

"Yeah, I would..." Amethyst muttered as she hung her head in shame. How could she have overlooked something so obvious?

"Alright, then try again," Mr. Dinger said, crossing his arms sternly, "And this time, make it sound sincere."

Amethyst took a deep breath to calm her nerves, then said, "I swear on my sopping-wet amethyst fuckhole of a cunt that I will never flash a male teacher again."

Mr. Dinger grinned, "Much better. Alright, you can go. But if I catch you flashing a male teacher again, I'm not going to be so forgiving. So no matter how much you like showing your vagina to men, you will keep your promise to me, correct?"

"Yes sir," Amethyst said with a blush, walking past him to get back to her books. It was going to be hard to resist showing off her hairy pussy to men now that she knew how much she liked doing it, but she fully intended to keep her promise to Mr. Dinger. Besides, she only promised to not flash teachers... and there were plenty of other males at this school alone who weren't teachers. She would just need to be more discreet in how she asked someone if she ever felt like doing it again, if only to avoid drawing unwanted attention to herself.

Satisfied with how much he played around with Amethyst, or whatever her name used to be, Mr. Dinger thought to himself about whether he should talk to one of the study groups at the library (or study pair in the case of the couple) or go somewhere else in the school.