Renjun had brought it up while the two were eating breakfast.
"You want me to choke you?" Jeno had sputtered, nearly dropping his coffee cup.
Renjun had just nodded cheerfully, as if he'd asked about the weather. "In fact...I prepped myself this morning if you wanna do it now."
"Who says I wanted to do it at all?"
Renjun just giggled. "You know you want to."
They stared at each other for a few moments.

And that's how they ended up with Renjun moaning in Jenk's lap.
"O-Oh...oh my g-gosh, Jeno..."
Jeno entered him from behind, biting his lip. He rested his forehead on Renjun's shoulder. "Shit. You're tight." He grabbed Renjun's hips, lifting him up slightly before slamming him back down. Renjun let out a strangled cry and Jeno smirked, giving the boy's thigh a gentle squeeze before returning to a bruising grip on the boy, thrusting up into him harshly.
Tiny Renjun was manhandled like a ragdoll and he loved it.
"Ah. Jeno, harder, please." He requested, his eyes fluttering shut. Jenk complied, his blunt nails spreading Renjun's pale asscheeks apart as he went deeper.
"Jeno...ch-ch-choke me n-ow, I'm ready." Renjun gasped, stuttering with each hard thrust.
Jeno moaned in response, he took one of his hands off Renjun's waist and loosely wrapped it around his neck. Not squeezing, at least, not yet.
"Ride me, sweetheart." Jeno whispered, his eyes nearly rolling back into his head as Renjun complied. He started with a few gentle squeezes before pressing his thumb directly over Renjun's jugular. The smaller cried out and his hips stuttered for a moment before he regained his composure, continuing to bounce up and down on the Jeno's cock.
Jeno pressed harder, groaning softly as Renjun's face slowly became red. Fuck, he looked sexy.
Jeno waited until Renjun's thrusts got weaker before letting him go, leaving the boy spluttering and gasping for air. Renjun braced his hands on Jeno's chest, using it as leverage to pull himself up and drop back down. Jeno started to squeeze his neck again, a grin on his face at Renjun's fucked-out look. "Even if you pass out I'm still gonna fuck you." He sneered, squeezing again. Renjun whined at the words, clenching tightly around Jeno's cock.
"Oh? You'd love that, wouldn't you?" Renjun nodded, his face slowly getting red again. "Yeah, I thought so." Jeno continued breathlessly. "You love to be daddy's personal sex doll, don't you?" He was nearing his edge, and by the looks of it, so was Renjun. "Y-yes, daddy..." His sentence trailed off into a groan as Jeno cut off his air once again.
Jeno could tell the boy was on edge. He waited for a few moments and then let go of his neck. Renjun sobbed, falling against Jeno's chest as all the blood rushed back to his head and his cum came out in little spurts all over Jeno's shirt. Jeno thrust up into him one last time, spilling inside the boy with a groan. "Fuck."
Both boys were breathing hard. Jeno wrapped his arms around Renjun, letting the boy snuggle into his arms. "Good?"
"Yeah." Renjun said happily, his voice hoarse and rough from Jeno's actions.
"Your bruises are gonna look so pretty. I can't wait." Jenk remarked, making Renjun flush.
"I always knew you were into that."