Crowley's always had his finger more squarely on the pulse of rumour than Aziraphale, for some reason. It's one of the ways he keeps track of the rumours about himself (and starts a few if there aren't enough). He long ago learned how to lurk in plain sight and never get noticed. People talk around him, and rarely worry about what he hears, while he hears everything and sifts through it for what he needs.
Right now, what he needs is more details on the students making people sign up for the stairs, so he nurses a coffee and his phone where he's likely to hear the most. He hears enough that he'll probably be able to pick them out if he encounters them. What he catches most though, is who they're asking and that lets him know exactly what bait to dangle in front of them.
Aziraphale is sweet and soft and fat and gentle, and they'll probably take one look and think he ought to use the stairs in order to lose weight. As if that ever changed who a person was, or what they were worth. (Everything. He's worth everything)
Crowley, while thin, passes the abled-assumptive test of no visible aids and no obvious differences, and they'll probably jump straight to the conclusion that he has no reason not to use the stairs except laziness. As if they can tell that by looking at him. (They can't. Nobody can)
Together, well, they can play off each other too. And if the students take the bait and come to them, well... He hides a curled lip and a silent snarl by finishing his coffee and heading out.
"I know you prefer the funny ones," Aziraphale begins, falling into step beside Crowley, "but I do think Shakespeare did an excellent job with Hamlet." It's an old familiar argument, worn smooth with time and repetition, and they can both bicker on it easily with half their minds on other things. ("Don't tell me details," Aziraphale had said when Crowley called him to arrange the apparently accidental meeting. "I need to be able to react honestly.")
"Alas, poor William," Crowley quips back, "I knew him well." He keeps facing forward, his mouth in its usual tight line, but behind his dark glasses his eyes flicker to his angel. With him on one side and the wall close on the other, he has easy access to support on both sides if he needs it.
"A fellow of infinite jest and most excellent fancy1," Aziraphale echoes, half quote, half agreement. "He had an excellent understanding of how people work and how that makes them interact, and Hamlet showcases some of that to perfection..."
Crowley lets the usual spiel wash against him, drawing comfort from its familiarity and dropping the occasional word in where expected. Inside, under the shield of old routine bickering, he's bracing himself for the confrontation to come and hoping that Aziraphale's "honest" reaction is a good one. He can take over himself if he has to, but sweet Dr Fell doing it will, he reckons, be stronger and longer lasting.
There's a goodly crowd where the corridors leading to the stairs and the lifts cross. Plenty of people to catch and ask to sign up. The pair of students feel sure that they're doing the right thing, helping the environment and making people healthier at the same time. A couple of older faces in the crowd stand out as professors: Dr Crowley sauntering along by the wall, and Dr Fell keeping up on his shorter legs, talking nineteen to the dozen about Shakespeare. Well, Dr Fell's talking. Dr Crowley barely puts a word in, like someone enduring one of the infamous info-floods, poor chap.
He'll probably be glad of the interruption, and everyone knows that Dr Fell is the sweetest of angels. This should be an easy pair of signatures to get, they reckon, and step forward together with their smiles and clipboards at the ready.