Story: Friendly Hentai Tome

 

The dangerous thing about Nabiki Tendo is that she's smart, observant, and thoroughly ruthless. This means that she's willing to do things that an ordinary person wouldn't. Sacrifice her morals, lie, cheat, redirect blame. It lets her get away with a lot. The audacity of it, taking advantage of the better nature of others. It's entirely possible for Ranma - as an example - to fold her in half when she tried her nonsense on him. But he doesn't. Because he does have scruples. There are things he will not ever do. She takes advantage of that. Exploits the oversight. It doesn't matter how much stronger an enemy is if they will not use that strength to its fullest, yes?

From this, she has taken on the title of Ice Queen of Furinkan. A cold yet beautiful maiden who will strip you apart for her own amusement. Indeed, Daisuke and Hiroshi were taking an enormous risk in playing with her using their new knowledge from the Friendly Hentai Tome. If she saw through it for even a second, she'd make their lives a total misery.

But it would be worth it. That's what both boys were thinking right now while watching Nabiki rub cream up and down her exposed legs. Worth it, worth it, worth it.

"Now boys, the first of you to get this right gets to lick some of this cream off my legs," Nabiki said, She planted her foot up on a pillow and wiggled her toes. While neither boy had a foot fetish, that could change quickly. "As your friend, it does pain me to see you falling so hard behind on your studies. So! Let's start with something simple, and give you a single lick for getting it right. Differentiate f(x) = (x^2)/2."

Both boys stared at her legs with abject, naked lust. Their mouths felt dry. They knew they were being played, that Nabiki had hijacked their little plan to corrupt them. But it was kinda hard to care about right now. When what really mattered was the answer!

"Uh..." Hiroshi burbled. "So... x^2 is just 2x, right? Then... You'd just divide by two and it would become... x?"

"Very good," Nabiki said, patting him on the head. "Now. One lick. That's all you get for such an easy question."

One lick, huh? Hiroshi got down on his hands and knees. He felt like he should be salivating but, you know, dry mouth and all that. Hrm. One lick. Just one lick. "Anywhere I want?" Hiroshi asked. "I just get one lick?"

"That's right," Nabiki said. Alright. Perfect. In that case - 

Hiroshi immediately kissed Nabiki's thigh. Then planted another quick smooch not far away from there. Then another. And another.

"Sneaky boy," Nabiki grunted, but she didn't say anything else. She simply lay back on the couch. "Alright, go ahead. If we weren't friends I wouldn't let you get away with - Ah!"

Sensitive spot located. Hiroshi attacked it mercilessly, but had to take deliberate care to ensure his tongue didn't come near the front of his mouth. The slightest lick and she'd kick him off.

"My turn!" Hinak chirped, and out of the corner of his eye, he could see that she was rubbing quite a bit more cream on her leg than Nabiki had on hers. Absolutely covering and caking it, and... Drool! While Nabiki's legs were works of art, Hinako was a tier above. A really healthy pair of legs, those! "So, how would you integrate x?" Hinako asked. "One lick, that's all you ge~et!"

"Oh!" Daisuke jumped out of his seat. "Integration is the opposite of differentiation, so it would be (x^2)/2!" he said, seeming quite satisfied. But... Daisuke, you fool! All Hiroshi had to do was lick this leg before he realised his mistake, then pull himself away from Nabiki and -

Liiiiick! He couldn't help himself. From the moment his tongue touched her leg, he'd trailed it from thigh to ankle, then run it around her feet and swirled her big toe into his mouth. It was like his body had done it automatically. By the time he'd realised what he was doing - 

"Oh, plus the constant c!" Daisuke sheepishly rubbed his head. "Ahahaha, yeah, you have to add that when integrating, I forgot..."

"Okay, you got it right, come and take a lick!" Hinako said, and the lucky bastard went for it. Ooh, Hiroshi was really steaming now! But, you know, neither of them was likely to forget the constant going forward now, so this was actually working.

He wasn't able to really think about the implications of that before Nabiki grabbed his head and turned him towards her. "Alright, Hiroshi-baby. How about this? If you get this next question right, I'll let you use those lips of yours on mine."

"What if I get it wrong?" he asked.

"Then you have to treat me to dinner," Nabiki said. Huh? So, either he got to go on a date with Nabiki Tendo, or he got to make out with her? That seemed solid to him. "But you only get the kiss for thirty seconds."

"Can I use tongue?"

"You'd be a lousy friend if you didn't," was Nabiki's reply. "No limits on the hands either, for the duration of those thirty seconds. Deal?"

Easiest deal he'd ever made. All he had to do was get this question right, and then - 

"Differentiate x^x."

... Huh? Differentiate... Huh? Daisuke frowned. There were various different rules for differentiation that he'd heard of. He'd used the most basic one earlier on. When you have x raised to a power, it's pretty darn easy to differentiate. He was also aware of what to do when raising a constant to the power of x, but that was a bit trickier. How was he even supposed to start - 

Then he saw Nabiki lick her lips, and reach out towards Sayuri, and as a taste of what he was missing out on the two of them started to kiss right there in front of him. Meanwhile, Yuka had moved to sit on Hinaki's face and Daisuke was doing the same trick he'd done to Nabiki, kissing all over the hot teacher's leg, making her squirm with sheer delight.

He'd never felt so motivated in his life. Check your notes. Check your notes... Chain rule! Was that it? Yeah, maybe that was it. This was a combination of two different kinds of functions, so - 

So...? Chain rule. Chain rule. Something about that was bothering him. How to differentiate a combination of two functions...? Something about that felt off. It was niggling at the back of his brain and- 

"Mmm, something wrong Hiroshi-baby?" Nabiki asked, hugging Sayuri close and turning her head so the other girl was more making out with Nabiki's ear. "Do you need a hint?"

Hiroshi tilted his head and looked her over with great suspicion and intrigue. What... was this feeling? No, not the arousal. He knew what that was already. This kind of prickling feeling creeping along his arms. Like goosebumps, threatening to get to his back and trail down his spine.

Was Nabiki manipulating them? No. Couldn't be. If she'd read the tome herself, she wouldn't have fallen under its effects. She'd have called them out already, or turned them into her slaves. Or... Was this a function operating off a function? Was Nabiki doing her own thing off the back of their thing?

That sorta made sense, in a way. You could almost think of it as 'raising the friendly hentai effect to its own power'. She was twisting and turning it around on them... On instinct? Yeah, on sheer and pure manipulative instinct she was using the same techniques being used on her back against them, but also doing her own thing. Like using her natural beauty to distract them. She must be like this with her own friends as well, to a point. Play nice with them. Still tries to use them to get what she wants.

In which case, maybe the smartest thing to do would be trying to take control over the situation...? Or should he apply his own 'chain rule' to resolve the thorny problem in front of him?

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