Kepler discovered and published a third law. This law provided a mathematical formula to determine the length of time required for an object to orbit the Sun based on the length of the semi-major axis (half the major axis) of the orbit.
Zayn blinks. The back of his neck feel strangely prickly, almost as if someone's watching him- he cranes his head to look behind him.
Niall's sprawled on top of Zayn's bed, an unopened textbook resting on his lap, remote tucked in his hand, the flat screen telly playing Neighbors nosily. He's not paying attention to it though, just pouting in Zayn's general direction.
“Niall,” Zayn sighs. “We can't-”
“Why can't we have sex?” Niall says in a voice that's almost at whining territory. “I've been dying to suck you off all day.”
Zayn gestures at the textbook in front of him. “You know why: the test. Which you should be studying for!” He lobs a highlighter at Niall's head and misses by a couple feet.
“I can't believe it,” Niall mutters, standing up and letting his book fall to his feet. “Your mum lets me- your boyfriend, might I add- sleepover, and all you want to do is study? And I was lying on your bed, I might add.”
“I don't want to study,” Zayn protests. “I just don't want to fail chemistry.”
Niall snorts and makes his way over to Zayn. “You sound like Liam now. So studious.” He squishes next to Zayn on the small swivel chair, something he does every time Zayn pays more attention to something other than Niall. He almost wonders if Niall purposely broke the armrests off just so he could squeeze Zayn out of his chair easier. After all, how does one accidentally break two whole armrests in the span of time it takes Zayn to use the bathroom?
“Besides,” Niall says, snapping Zayn out of his thoughts. “Don't people always have sex before sports or whatever? This is like sports for the mind. We should have sex.”
Zayn raises an unimpressed eyebrow at him. “Nice try. You're suppose to not have sex before sports.”
“Oh.” Niall mulls it over for a few seconds. “Then we should have sex, because schoolwork is not at all like sports.”
“You're not going about this whole seducing thing very well,” Zayn tells him, idly highlighting a sentence on the page that looked vaguely important.
“Oh, I'm supposed to be seducing you now?” Niall says, then flails around in the chair unsexily until he's behind Zayn, legs bracketing his torso.
“You want me to have sex with you, don't you?” Zayn points out. “Doesn't seducing people usually come before that?” He puts his marker to the paper to highlight another sentence bright yellow, then completely misses his mark when Niall leans forward and blows softly on his ear.
“Dammit, Niall,” Zayn scrubs at it uselessly, smearing the color around with his finger in a futile attempt to erase the mark. “You know how my ears are sensitive-” the last part of his sentence is spoken with a shudder as Niall sucks behind his earlobe.
“Yeah, like that?” Niall murmurs, a smile curving against the soft skin.
Zayn doesn't say anything, just stubbornly focuses on his book.
Ptolemy's astronomy was based on a geocentric, or Earth-centered, system.
Niall bites at Zayn's ear and slowly slips his hand around Zayn's waist, fingers toying at the hem of his shirt.
Using this system, he developed a method to predict the positions of the planets and other celestial objects at any time during the year.
He lightly rubs at Zayn's stomach with his thumb, just enough to make it tickle, and then places his hand at the button of his trousers, fingers just resting there.
These positions were used for agricultural planning. For instance, when a specific planet or star was in a certain position, it would signal the time to plant corn.
Niall starts to unbutton Zayn's jeans and Zayn's hand flies down to cover Niall's with his own. “No,” He says sternly.
“Come on,” Niall whines, then bucks forward so Zayn can feel his hardness against his back. “You don't even have to take off your pants all the way, just lemme-” He tries to break free of Zayn's hold to no avail. “Just lemme suck you off, or maybe a nice handjob- you don't have to even do anything, just let me-”
Zayn bites his lower lip, already getting mildly hard from Niall's words. “St- stop,” He chokes out. “I haven't studied all week and Mum's gonna get me a tutor if I fail this test, and it's probably gonna be Liam, that smug little brat-”
Niall groans. “Stop talking about other people when I'm trying to fuck you.”
“We're not going to fuck,” Zayn says, trying to sound firm but sounding more desperate then anything. “We're going to study. Or at least, I am.”
Niall sighs. “Fine.”
Zayn turns his head to look at Niall dubiously. “Really?”
Niall nods. “Why don't you read it to me?”
Zayn narrows his eyes- he can still feel Niall's cock pressing against him insistently, but it's not like he's not going to take advantage of Niall's sudden compliant-ness. “Okay. Well, I was just reading about Ptolemy and the third law of- something, um.” He scans the pages, looking for his previous paragraph for a few seconds before giving up and just picking a spot at random to read from. “An ellipse can be folded vertically or horizontally to form two identical halves,” He reads, trying to ignore the way Niall's breathing lightly at his neck.
“Uh huh,” Niall mumbles, resting his chin on Zayn's shoulder. “Go on.”
Zayn's pretty sure he didn't imagine the flicker of tongue he felt on the side of his neck. He's also pretty sure Niall's deliberately trying to drive him crazy. “Each of the "fold lines" forms an axis that divides the ellipse into two equal and symmetrical halves.” He continues on, helpfully pointing at the illustration demonstrating the axis on the ellipse.
“Hmm,” Niall breaths out, hot air warm on Zayn's neck and ear and Zayn tries to hide the way his spine automatically straightens.
“The longer line is called the major axis,” Zayn reads, and Niall lowers his head to kiss the crook between Zayn's shoulder and neck, “and the shorter one is called the minor axis.”
“Yeah?” Niall gives a short suck to his neck, making the blood bloom beneath his lips. “Fascinating.” He grinds forward a bit, and Zayn's eyes squeeze shut.
“Go on then,” Niall prompts. “Keep reading.” He reaches a hand out to tap at the textbook, and drops it again to rest right at Zayn's crotch.
“Stop trying to seduce me,” Zayn says firmly, removing Niall's hand from his crotch. “Ow, don't hold onto it, that fucking hurts.”
Niall laughs softly into Zayn's ear. “Don't be such a priss.” He nips at his jaw.
Zayn scowls and Niall sighs.
“I remember a time when you used to like me seducing you,” Niall says teasingly, muffling his smile into Zayn's cheek. “Good old days.”
They sit in silence for a few more seconds, Zayn pretending to be intently reading his text but really just focusing on the way Niall's cock is practically throbbing against his body and the way it just won't go away.
“Oh for fuck's sake,” Zayn groans, slamming his textbook shut and sliding off the chair and onto his knees. “I'm so going to get you back tomorrow,” He mutters before unbuttoning Niall's trousers, ignoring his shit eating grin.
“I can't believe I let you fuck me again last night,” Zayn fumes, pulling his keys out of his apartment door. “We only got like three hours of sleep last night- how the hell are you so cheery?” He scowls at his boyfriend, who's stuffing a muffin into his mouth, humming some cheesy Justin Bieber song.
“I dunno,” Niall shrugs, still smiling infuriatingly. “I was able to fuck my boyfriend three times last night,” He shrugs. “That type of thing usually makes people happy.” He gives Zayn a pointed look.
“Yeah? Well I'm going to have to sit in class all day with a sore ass, so thank you for that.” Zayn complains, stuffing his keys into his pocket.
“Hey, you weren't complaining last night.”
“Will you-” Zayn makes a frustrated sound. “Shut up! I'm going to fail this test and Liam Fucking Payne is going to have to tutor me and it's all your fault!”
“Are you being a bit dramat-”
“No!” Zayn stomps off. “I'm going to let Liam Payne fuck me, just to get back at you!” He yells over his shoulder.
Niall just laughs.
(He probably knows that they're gonna go for a couple more rounds in Zayn's bed later. That little twat).