Charleston is referring to this incident, and also addressing the fact that Charleston and Perverto’s thing in November was supposed to be them going to get a thingy that may seem unnecessary considering how they’ve already jumped universes once or twice already. So here’s why they need a device to detect cross-universal anomalies and, perhaps, travel to and from other universes:
1) Such things are really neat.
2) Previous mode of travel #1 (Azurank in a limo) is only available for special occasions.
3) Previous mode of travel #2 (Floyd the Demonic Garbage Truck) is, as Perverto says, only able to break through in relation to Riverwood and is unable to be controlled. This is why Perverto and Charleston wound up getting so lost that they wound up in a no-name midwestern town instead of Detroit which, honestly, should have taken an afternoon to get to from Riverwood.
So, basically, they need a neat and mostly reliable way to get things done. I’d say that Friday’s comic is going to be less exposition heavy, but dear god, it’s not. It’s really not. I’m so sorry.