It's more a courtesy than a rule that they don't take advantage of anyone that's been unfortunate enough to be downed with a truth serum. Unfortunately, accidents happen.
More unfortunate still - Jason does it to himself. It's the most blatant show of self-sabotage he's ever witnessed or experienced; a feat, considering Jason has gotten himself killed (and set himself up to die the exact same way when he got a second chance, to boot).
There's no one to be mad at except for himself, but Jason can't even be that because he's too busy being mortified at himself and the truth he owns up to.
It's a joke (he thinks?) between them that Tim and Kon want to fuck him. It's some stupid way that they tease each other. That Jason thought about it isn't something anyone needed to know though.
But they're all working in the Cave as they wait for the truth serum to wear off. And it's quiet, boring, so when Tim gets a text of course Jason asks who it is. And when he finds out it's Kon, obviously Jason asks what he's up to.
It doesn't matter if Tim and Kon were actually texting about it or if Tim says it strictly out of habit, but Tim says, 'Kon was checking in to see if you'd let us fuck you yet,' and Jason somehow interprets the statement as a question.
The words leave his mouth unbidden and all Jason can do is stare into the middle distance, straight faced and utterly dissociated because Jason, in no uncertain terms, says as blase as anything, 'Yeah, I'd probably let you fuck me.'
And Batman's no meta rules be damned, Kon is there as if beckoned, smile wide and hand propped just behind Tim on Tim's chair, the picture of casual when he says, 'Hey, hi. What're we doing?'
All the while, Tim stares, wide-eyed and in awe because 'What?'
At which point Dick also intervenes, because 'What? 🙂'
Embarrassed as Jason is, he does his best to brush it off. The pink dusting his cheeks gives him away, but he glowers to try and offset it. Intimidating as he tries to look, even Jason knows he only looks sulky at best. Still, he double downs and says it again, 'I'd probably let Tim fuck me.'
Kon clapping Tim's shoulder and swaying them side-to-side, victorious because, 'We're so in.'
Which leads to a playful scuffle between Kon and Jason because Jason tells Kon that he's not going anywhere because Jason said Tim, only for Tim to get offended because why not Kon?
Which leads to a second unfortunate accident: 'Because he's not Robin.'
Jason doesn't hang around to see the aftermath of the mortifying truth. He slips right out of his chair to take cover beneath the table, hood pulled over his head and drawstrings pulled tight to allow more give to strangle himself fuuuuuuu-
Meanwhile, the peanut gallery: 🤯😳🫢
And then Tim peers under the table, 'Yeah, we can do that.'
Even Kon crouches down just to bump his fist to Jason's, 'Respect.' Because he gets it. ;)
It's all too much for Jason's maiden heart to bear, so he groans and tells the both of them to shut up while he crawls blindly out from beneath the table so that he can run and hide in the manor and maybe tell Bruce that Tim snuck his boyfriend past city limits.
Only to bump into Dick's leg. Who Jason somehow forgot was there at all. He drops his head to the ground, overheated from the levels of mortification he's experienced in less than five minutes.
Through Tim and Kon's laughter behind him, their jokes about missed opportunities, Jason notes that Dick is suspiciously quiet.
So, like the fool he is, Jason looks up to see Dick's expression.
He's scowling.
Jason groans to himself and drops his head back to the floor. Curled small in a ball at Dick's feet because why's he scowling? He's mad that Jason would defile the good Robin name (again)?
But Dick nudges him with his foot, both gentle and not, prompting Jason to sit up and glare at him, ready for a fight.
'I'm Robin.' Words Dick never thought he'd say again, but here he is. Offended. Petulant. Jealous. Because if Jason wanted to be fucked by a Robin, why not Dick? 'You wouldn't want me to fuck you?'
Which leads to the most unfortunate accident of the night. The damn truth serum must react more to things Jason feels strongly about, because he's embarrassingly enthusiastic, emphatic when he proclaims, 'Of course I want you to fuck me.' And more embarrassingly still, 'You're the only guy I ever want to fuck me. You could bend me over and fuck me wherever you damn well please and I'd say thank you.'
The force with which Jason slaps his hand over his mouth would be painful if he weren't currently in another plane of existence and not present to register it.
Dick being in a similar predicament, awestruck because Jason is that down bad. Overwhelmed, mind racing because like - Dick being the only one Jason's ever wanted?? Sexually, Dick's down. Romantically, he needs to buy a ring.
Even Tim and Kon are dumbstruck, watching with wide eyes at this sudden development. If only because Kon is a good friend, he shuffles over to Jason and bumps their fists again, all camaraderie when he claps Jason's shoulder, says 'Nice,' and backs off with hands raised in placation because Dick's been given the green light for less than a minute and he's already territorial af.