"...my natural log," Antonio whispers. "is rising. You must be an inverse function."

Lovino's hand shakes as he tries to copy the calculus notes from the projector onto his paper while at the same time ignoring Antonio's antics. The professor drones on.

"I wish I was your derivative so I could lay tangent to your curves."

"I've heard that one before, idiot," Lovino mumbles.

"You can be my second derivatives and explore my concavities."

Lovino's hand stops writing.

"Third derivative, we can jerk."

Lovino's entire body convulses. He actually understands that last line and he grips his pencil hard to stave off his laughter.

"The point of inflection," the professor says. "based on the sign of a function's second derivative, f double prime of 'x', determines whether the graph of a differentiable function, f of 'x', is concave up or down—"

"I'll be sine squared," Antonio says. "and you'll be cosine squared."

"Taking the inverse of the second derivative, we get—" says the professor.

"So we can become one."

Lovino snorts. Loudly. Several of his classmates in the row directly in front of him turn to give him a look. He tries to hide his grin with his sweater.

Antonio scoots his chair closer. They're so lucky to be sitting near the back of the lecture hall. He places his hand on Lovino's leg, not caring enough to actually listen to the prof and take notes of his own. "You and I add up better than a Riemann sum."

Lovino wants to ignore him.

"Speaking of Riemann sums, God knows I'd kill to calculate the area beneath your curves…" Antonio's hand is playful and warm. "Won't you show me what's under your radical?" His hand trailed up, threatening to dip under Lovino's shirt, or, God forbid, his jeans. "That would be the rational thing to do," Antonio adds.

"As opposed to what—your hand going down my pants in the middle of class?"

Antonio shrugs and smiles lightheartedly. "What can I say? Your body is an asymptote and I'm the graph of 1 over x: I want to get really, really close to you."

"But not touch me? You're such a tease." Lovino smirks.

"You love it when I tease you," Antonio whispers. His hand moves to Lovino's back, under his t-shirt, and smooths along his spine. "Here's a nice vertical asymptote…"

Lovino tries not to lean into the touch. "And, much like the graph of 1 over x, your limit doesn't exist."

"There's no limit to what I would do with you," Antonio purrs. "or to you. What do you think L'Hôpital would say our limit is when I'm over you?"

Lovino wills his hand to start writing but it just doesn't move. "It depends. Am I getting closer to zero, or to infinity?"

Antonio reaches over and squeezes his leg with his free hand. "Infinity. Always."

"Then that would make our limit zero as I approach infinity. Nice try, slick."

"But Lovi, the derivative of my love for you is zero. Because my love for you is constant."

Fucking dammit.

"—rate of change. Remember that from yesterday? By finding the second derivative, we can see how the rate of change is changing over a period of time," the prof says. "Velocity. Notice how—"

"Pi over 2," Antonio says.

"What?" Lovino says.

"You're the sine of pi over 2," Antonio says. He gets close enough that his lips brush against Lovino's ear. "The 1 for me."

Lovino blushes.

"I'm the only significant figure you need," Antonio murmurs.

Lovino closes his eyes and smiles. "I can't believe you're actually turning me on in the middle of class." He turns his face and Antonio's emerald eyes are right there, inches away, twinkling mischievously. "I might just have to punish you later."

Antonio's eyes glaze over.

"If I'm sine, then you're cosine," Lovino says quietly. "I wanna make a tangent."

Antonio runs his thumb over Lovino's bottom lip. "I wish you were my calculus homework," he breathes. "Because then you would be so hard...and I'd be doing you all night—"

"Excuse me." The professor's voice comes out harsh and loud. "To the two gentlemen canoodling in the back: don't think I can't see you."

The lecture hall goes silent. Instantly, eighty pairs of eyes turn to stare at them.

Antonio and Lovino jump apart, startled to be put right on the spot. Lovino blushes and blushes and fucking Antonio. He shrinks in his chair, willing himself to morph into a dust ball and fly away.

"I remember specifically asking you all to focus and pay attention during the lecture," the prof says coldly. "Either you two smarten up, or go canoodle in the hall where the rest of us don't have to see you." And Lovino wants to die.

When he looks at Antonio, he's blushing, too, a bit. "Sorry, sir," Antonio says, and gets up, grabbing his textbook and notebook and backpack. "We'll canoodle in the hall. Sorry to disturb you guys." He gently takes Lovino's elbow. Somehow, Lovino dumbly follows, grabbing his belongings and letting Antonio guide him out the door.

"What the fuck," he says angrily once they're outside. He yanks his arm out from under Antonio's touch. "We just got kicked out of class because of you!"

Antonio rolls his eyes. "Thank goodness. I was dying of boredom back there."

"I don't think you understand the gravity of the situation. We. Got. Kicked. Out. Like we're fucking thirteen-year-old delinquents."

"Aren't we? Now come on, let's get out of here." Antonio slips his arm around Lovino's shoulders.

"And do what?" Lovino hisses. "Our homework?"

"Canoodle," Antonio says simply, pulling Lovino down the hall. His hand slips down Lovino's back. "I do believe you said something about making a tangent."

Lovino goes beet-red. With anger? Embarrassment? The world may never know. "I'm gonna fucking kill you."

Antonio squeezes Lovino's butt. "Sure, sure. But first, I want to expand your polynomial and insert myself into your solution."

A/N: Bahahahaha. I never get tired of writing these.

How about some advanced math and physics lines for y'all? Hope you enjoyed. Happy Talk Dirty to Me Day, everyone. Or, to the rest of the world, happy May 24th. (Or 25th, depending on where you're from. B) )

Why do I legit think this is something Toni would do? Lmao.

Thanks for reading! See you next year!

Stay classy.