Wait, that's the same guy? I thought the LaVey lookalike wasn't the same dude as the ponytailed gamer.
He was the one who didn't have a ponytail in the guest page (g2).
The guest page would appear to serve little purpose unless the buxom wench is Cherry, the Dianic thing on Wednesday is at least the
kind of event where Cherry might summon a demon and get herself hurt, and the guy in the black t-shirt is someone who's closer to Erin than any of the others are. (And there's perhaps a suggestion that he was somewhere between guiding and manipulating Erin.)
256 confirms Erin was indeed in a relationship with someone who bought her what appears to be the ceremonial blade whatsit that she used in 198. And that person wasn't a buxom wench.
The Dramatis Personae page (which ignores guest pages) gives 483 as the first appearance of Aiken.
But 276 would certainly appear to imply that that's Aiken with Cherry in hospital. There he certainly looks more like the guy in the guest page. And frankly, using a picture of Cherry with someone who wasn't Aiken to illustrate a scene where Cherry talks about discussing Erin with Aiken, would have to be considered serious misdirection.