My favorite jonelias AU will always be Jon the Monstrous Sugar Baby™ no matter the context. I love it in the university-era, but I also just really love the idea of Elias taking an entirely different direction to making Jon his Archivist and taking on a caretaker role instead of a distant manipulator.
And sure, it’s fun if the love he shows Jon is just a manipulation tactic, but it’s more fun if it starts that way but becomes sincere over time as Elias genuinely falls in love against every single instinct he has.