He feels an open summons and lets it grab him -
"Awwww," giggles Tony. "It's less weird for me, mine are on and off all the time."
"I'd imagine. Yeah, I just don't feel like I am actually hugging you, I feel like I am sort of awkwardly avoiding hugging you."
"Put your wings back on, then!"
"Hey, humans, am I going to want to be incognito a lot in the next while, you think?"
"Bet not. And you've still got the coat for emergencies," says the Joker.
Cam sprouts his wings and tail and properly hugs Tony.
"Aww, tail," she says delightedly, hugging him back.
"You are both adorable," says the Joker.
"Yes," Cam agrees. "How long are you planning on keeping us?"
"How long do you wanna be kept?"
"I won't even start having mixed feelings about it till the next time we get a Limbo concordance, because I don't wanna miss a letter from my parents, or a chance to give them one, but if you just sort of leave me running around off-leash I will do things and if there are any you'd take offense to and send me home for I'd rather know in advance."
"I'm pretty hard to offend."
"All right. So keep me for eight years and don't do anything that makes me want to murder you and we should be good."
...John looks like he really, really wants to say something and doesn't quite dare.
Cam raises an eyebrow at John.
"I just have this feeling," he says, eyeing the Joker, "that he's the type to take that kind of deal as a challenge."
"To what, make me want to kill him?"
Cam looks at the Joker.
"Well, not until this Bane thing is settled," he says. "And then - maybe, maybe not."
"If you want to see which kinda wings your future neighbors have you don't need me to do it."
"Believe me, I know," he says. "It's the game."
"Does it make any difference that I don't think it sounds fun and would rather be giving nice presents to the impoverished rather than worrying about you trying to provoke me?"