Not feeling it today. But I thought that I would delve into marvel horror.
Sleepwalker
The host is less important because there's a built in time limit. There's a very serious risk of being driven insane by being the Sleepwalker's portal. And it doesn't just choose good people as hosts. The name is a title, like "officer." It is tasked with chasing down escapees from its own dimension. And it occasionally feeds off the fear and negative energy that evil-doers give off. The escapees are only able to breach the mindscape during times of widespread turmoil (nuclear disasters, plagues, war). So a lot of these dream demons have had time to get comfortable and adapt to a new environment. My version of the Sleepwalker would be more horrific looking, like a rotting alien corpse adorned in something inbetween sewage soaked rags and cobwebs. It would still have the eyebeams but could also subtly alter reality in the immediate surroundings to be creepier like making the walls bleed or creating realistic hallucinations/nightmares. And it would take great pride in its work, like a very by the book police officer. Some of the individuals it hunts are humans who have been sold dreams by one of the escapees. They might literally be living in luxury when Sleepy shows up to collect. His "boss" btw is Nightmare. But he is basically outsourcing the work.