"Okay," Kakashi said, a wide grin on his face as he stood before his students. "Since the ninja academy is crap at this kind of thing, I feel it is my duty to tell you three about the birds and the bees."

Sasuke, Naruto and Sakura stared blankly at him for a moment.

"But, Kakashi-sensei, we already know about -"

"Sakura, you should know it's rude to talk during class," Kakashi told her, still smiling brightly. He was enjoying this. "Okay - so sex is when the penis enters the vagina. Well, straight sex at least, but I don't think we need to go beyond that for now. I believe you're rather well-informed on the other matter." He stole a glance at a glaring Sasuke and a blushing Naruto, before continuing. "Because sex inevitably means pregnancy or disease, beside a heck-load of fun, remember to wear a condom. Don't worry about sizes, condoms are one size so you mustn't fret over having to get mini-protection for your small manhoods. Naruto - stop giving me that look, you have small feet and I think we all know what that means." Kakashi just smirked at the glare he was receiving. "And Sakura - don't listen to boys and their 'I'll withdraw in time' or 'you can't get pregnant the first time' - men lie. A lot. So make him cover it." He paused. "Any questions?"

There was a moment of still silence, before Sasuke raised his hand.

"Sa-Sasuke! What are you doing?" Naruto hissed, but the Uchiha just ignored him.

"Sensei, is it normal for people to yell food products - let's just say, ramen - during their orgasms?"

Naruto's eyes grew wide. Kakashi just chuckled.

"Now, now, we mustn't judge," their teacher told them. "Some people just have odd fetishes. We're all different."

Naruto was glaring daggers at his smirking raven-haired friend, before an evil smile grew on his own face.

"Sensei - is it normal for people to cry after sex?"

This time, it was Sasuke's eyes that grew wide.

"Kakashi-sensei, please explain to Naruto how it's perfectly normal to cry during the post-coital moment, as sex is a very emotional experience."

"Well -"

"Oh, boohoo, I got topped by my rival, poor me," Naruto mocked, before erupting into laughter.

"Now, now, Naruto -"

"Is it normal, sensei, for a regular, blond, teenage boys to take longer than average to, shall we say, rise to the occasion?"

Naruto's laugh stopped abruptly. "Well," he began mumbling. "Sensei, do you think raven-haired Konoha prodigies should yell 'DIE, BROTHER, DIE!' whenever very foxy, future-Hokages get them excited?"

"Interesting question -"

"Well!" Sasuke, rather uncharacteristically, yelled. "Is it normal for stupid, Uzumaki dobes to want their partner drenched in chocolate before agreeing to kiss their toned, muscular body?"

Naruto blinked at him. "I thought you liked that?"

"It's the point of principle!"

"GAH!"

"Now, now, both of you need to be quiet," Kakashi finally silenced them. "We're all different and I think we need to understand that. No, it may not be normal to yell food products, or cry - seriously, Sasuke?"

"Sometimes during sex too -"

"Dobe."

"Well, it also may not be normal to take time to get an erection - especially at your age, or to yell familial threats during sex, or to refuse sex without the involvement of chocolate, but everyone is different and we should respect that. Just because it's not normal doesn't mean it's abnormal."

"But, Kakashi-sensei, that doesn't make any sense -"

"Sakura, what have I told you about talking over me?" The pink-haired girl shut her mouth quickly. "In fact, maybe I should tell you about some of my odd experiences in the field of love-making."

There was a moment of silence as that sentence set in, before a flurry of voices said:

"No, really, Kakashi-sensei -"

"That's not necessary -"

"I think we know -"

And a reply came:

"My first time -"

"Oh gods…"

Kakashi, looking at the freaked out expressions on all of his students' faces, blinked. "You really don't want to know about the birds and the bees?"

"I just…" Sakura trailed off, and then Naruto filled it, "we already know all we need to know."

"Well, as you should all know, 'sensei' literally means 'one who has come before'. I'm sure I can tell you lots of interesting things to add to the sensuality of making love…" he paused, glancing at Naruto and Sasuke. "…between two of the same sex as well."

The blond and raven rivals glanced at each other, before looking back at their teacher.

"…what kind of things?"

"Naruto!! You can't be encouraging him!!" Sakura cried.

"Well," Kakashi began. "Ever wondered how to make your orgasms… longer?"

"Sensei!"

"You can do that?"

"SASUKE-KUN!!"

"Of course, it's quite simple really… still don't want to learn about the birds and the bees?"

There was a pause.

"Start talking."

"Make it sharp."

"Can we get homework too?"

"I'm with Sasuke on that one."

"More than just that one."

"AHH!" Sakura was left crying.