let's talk about sex, baby.
Dib has never spent much time wondering how he would feel about the inevitable Sexual Education Seminar that every child aged eleven and up knew would plague their school one day. If he did wonder how he would feel about it, Dib's best guess would have been along the lines of indifferent or bored or, at the very worst, mildly creeped out by the gym teacher saying the words "penis" and "menstruation" and stuff.
It's mid-December and Dib is eleven years old, fast approaching the end of his first semester of fifth grade. His father is the famed scientist Professor Membrane, and Dib himself has an IQ that's nothing to sneeze at. He's read books and knows how sex works and he stopped being grossed out by the concept a year ago. So when Ms. Bitters flings the classroom door open and directs them to the gymnasium with a sharp finger and says, "It's time for your childhood to be thoroughly obliterated. Go to the gym," Dib knows what's coming and does not expect to be made particularly uncomfortable. The class files down the hallway in a single file line like ants towards the gym.
The bleachers are sticky and smell like Poop Cola was spilled all over them two-thousand years ago and never mopped up, and Dib takes a seat next to Zim on the top leacher. There's something kind of gross about knowing he's going to be sitting next to his alien mortal enemy the first time Zim learns about sex, but then again, it also promises to be hilarious. After all, even if Zim were human, Dib has a feeling he wouldn't take the revelation about the human body and its post-pubertal functions very well.
"I hope you have your bucket at the ready, Zim," Dib says smugly, crossing his arms and leaning against the wall and then thinking better of it when he feels still-damp wads of gum stick to his coat.
Zim whips his head around to narrow his eyes at him. "Eh?! What are you talking about?"
"You're already stupidly squeamish about germs. Well, this is the Sexual Education Seminar. Germs are going to be the least of your worries when you learn about all the stuff humans get up to when we get older!" Dib cackles, remembering how disgusted he'd been when he was seven and learned where babies came from. It's a pipe dream, but he wouldn't be surprised if Zim just squeals in horror and flees straight back to Irk.
"Your stupid Earth seminars don't frighten me, Dib-slime," Zim sneers, crossing his legs primly and turning his attention to the front of the gym, glaring over the heads of their classmates. "And I have nothing new to learn from this seminar. You think I don't know every trivial, miniscule detail about you humans?! I am an invader! I AM ZIM!"
"Shut up!" the gym teacher screeches from the floor. She stands next to a rolling blackboard with the word SEX scrawled across it. "I want everybody's attention now!"
"Just wait," Dib says sotto voce to Zim, who sits with his spine straight, expression alert as he frowns down at the chalkboard. The coach pulls out a collapsible pointer and smacks the word SEX with the tip.
"The key to having safe sex," she roars to the children, "is to wear a wedding ring! Now get out."
That was anticlimactic. Their classmates stand and shuffle off of the bleachers and towards the gymnasium doors.
"That was stupid!" Zim sneers, standing and marching down the bleachers. Disappointed that he didn't get to see the alien gag at a picture of a placenta or something, Dib scurries after him.
"There's probably going to be a sex ed class when we get to high school, Zim!" Dib says sharply. "And then you'll throw up! Probably like a frog, where you just spit your stomach out and kind of…pick the—the stuff out."
Zim peers at him oddly over his shoulder. "Why would I do that?"
Dib jumps the last few bleachers and lands in front of Zim. He stands his ground, smirking at him. "Because you're going to learn about sex and you're going to be horrified like the alien you are."
Zim frowns. "I know what sex is."
Dib falters. He wasn't expecting that. "You do not!"
Zim's face contorts with rage. "YOU DARE CALL ZIM A LIAR?"
"What is it, then?" Dib snaps. "What is sex, huh? Tell me!"
"MORONIC BOY!" Zim snarls. He balls his fists at his sides, staring down at Dib from the last bleacher. "It's how your species reproduces!"
Dib folds his arms, unconvinced. "Okay. How does it work?"
Dib wishes he'd never asked. With a furious cry of "It's basic human biology!" Zim launches into a loud, detailed, and startlingly accurate rant regarding human sexual reproduction. Dib has never been so upset by the words "vagina" or "orgasm" in his entire life.
"I researched your horrible species within minutes of arriving on this wretched planet, Dib-stink!" Zim concludes sourly. "I know all about your disgusting needs and icky bodily secretions!"
"I'm going to throw up," Dib says reproachfully, feeling the blood drain from his face and a churning in his stomach. He doubles over slightly, and feels a chilling shadow fall over him.
"Zim!" Ms. Bitters barks. "You've made Dib deathly ill. What did you do?"
"Nothing, Ms. Bitters," Zim says, clasping his hands together and staring up at her with wide, revoltingly innocent eyes. "I was just finishing telling the Dib what a period is, because he is very stupid and doesn't know what a girl-human is."
Ms. Bitters's eyes turn to slits and she bends over him with a hiss. "You come from a broken, sordid home, Zim. Take Dib to the nurse."
"Yes sir!" Dib doesn't bother resisting when Zim hooks a hand around his elbow, claws digging into his flesh, and marches him purposefully out of the gym.