Mm, yeah. This wouldn't be one of the Chains he himself is Contracted to in canon, but rather, a Chain that he often uses in a partnership with one of his closest people -- it's Contracted to Sharon Rainsworth, but she has it ride around in Grown-Up Kevin Break's shadow a lot of the time so she can use it to eavesdrop. And, since it's capable of creating portals through shadows, Break occasionally uses it to disappear into cabinets and pop out from beneath tables. (This ability would be restricted in Emp, since there's not much by way of Abyssal influence to strengthen it. He could pop to and from work, perhaps, but not all the way across the island or off of it.) Our idea was that he'd meet the Chain in a time bubble after Sharon had relinquished her Contract, so the Chain would remember him, or rather his future self, and come to investigate.

The catch here is that the Chain in question is a flaming purple unicorn. Between Celestia and Peromei, Kevin's got a penchant for unicorn critters lately. The Chain being willing to eventually Contract with him when he canonically is given the Mad Hatter would be a nice mark of how he's become his own person in game regardless of Xerxes Break, and I also liked the idea of his old shadows becoming something he felt he could use, rather than a nasty reminder of his darker thoughts and insecurities, something to be punted away.

I'm super happy for this to be a slow-burn plot with proofs and crystals and I certainly wasn't going to have him go for a Contract as soon as he sees the thing, but if all of this sounds too special snowflakey, I'll drop the idea.