Jason sat uncomfortably in his seat, squishing in the mess his boyfriend left in his diaper, Surfjan's shit, and bit his lip in restrained ecstasy as he felt it spread across his rear. Why did it feel so good? All he could think was this was his boyfriend's mess, his boyfriend's, proof that he was Surfjan's boyfriend, and the more he thought about it, the more obsessed he became. He was blushing right now, panting as he gently rubbed his padded rump against the cushion, still continuing to think this was his boyfriend's poop in his diaper as Surfjan drove, that stupid, smug grin still on his face from having gotten lucky. He didn't even seem to notice, or care, that Jason was panting in barely-repressed bliss.
It must've been an effect of the app, or something, if this was normal in their world now, Jason could never imagine himself being turned on by another dude's shit before. Maybe it got it's wires crossed because he had been fucking him before? Whatever the case Jason could barely focus, he was so overcome with lust, his erection throbbed in the padding, begging for release, begging for Surfjan. Surfjan had claimed him with such a filthy act and Jason couldn't get it out of his head.
He fished out his phone, looking to try and generate another sentence on... something. Something to alleviate the frustration he found himself struggling to deal with as he humped the padding. The stench of his dirty diaper filled the car and it smelled just like Surfjan, it was almost impossible for him to focus as he used the app again, not really sure what he was scanning for really. He was in too much of a state of arousal to really pay too much attention.
Finally it seemed to pick up something and generate a new sentence. "This young man is wearing a diaper recently soiled by his handsome boyfriend."
Jason groaned, the sentence must be about himself. He continued grinding his messy rear against the car seat as his boner throbbed, looking down at the sentence. He could easily undo all this, all the weird diaper shit, but at the same time... he couldn't deny a part of him was craving even more out of this. He looked back at Surfjan, still driving along, ready to show all the frat bros his new diaper-bound boyfriend. Jason continued to fixate on the sensation and smell of it, something he could only feel was proof of Surfjan's true love for him. He couldn't deny that it felt so good.
He leaned back with a euphoric squish, looking at the app again, trying to focus and decide what to change...