The Book of Demogorgon Stalker

[Splash]

Middle bottom would work for that though. I don't think it should feel entirely hopeless for anyone without flying or who can't move through figures. If the opponent wants to risk OMs to escape I'd like to see that interaction, which wouldn't happen often if you can just have a demo placed on either side of the portal. Plus they don't really function as guards anyway so it'd be a weird way for them to play theme-wise.
If you can break engagement and run for the portal power to ya. So running two demos would mean (if you were portal guarding) instead of breaking engagement and moving 6 to escape you'd have to move 11 and break engagement again. Running three would have all escapes blocked, but at that point you've spent 525 points just to counter non-supers that you need to wound first.

I support middle bottom space.

edit: just in case middle bottom is unclear I mean the one with three connecting equidistant spaces