Dreamspace
Dreamspace is an alternate reality made up of forgotten places, people, and objects. It's essentially made up of a lot of liminal spaces, each one appearing similar to the real world but with something off about it: too vast, too repetitive, too empty.
Each space is completely empty and devoid of life. You are alone, and there's a kind of eerie atmosphere to it. Spend more time there, though, and you will realise that it is safe— there is nothing hiding in the dark, nothing out to get you. Here, no one is watching. There are no responsibilities, none of the stressors of regular life. It's peaceful, freeing.
Almost every space has a spot where the real world can be observed (eg. a reflection in a river). You can choose to see whatever you want, follow whichever person you desire.
Visitors
There are a few ways non-watchers can enter dreamspace. This is, however, quite rare.
dreaming
The most common way is through dreaming, hence the name, dreamspace. There are places in the real world with a strong connection to dreamspace. Being in these areas for too long, as well as a personal inclination towards this world (eg. strong imagination or escapism) can strengthen individual connections with dreamspace too.
With a certain degree of connection, a person can end up entering dreamspace in their sleep. They don't have any powers like the watchers, but can interact with the world as if it were real. They are also unable to die here (will just wake up), and will fade from the world when they wake up in the morning.
entering
Some places in the real world have such strong connections that a certain object or spot will act similar to a "portal", pulling people with strong enough connections into dreamspace when interacted with.
Usually, the person will eventually end up back into the real world (like a flash- one moment you're in dreamspace, the next you're back in the real world). The more time one spends in dreamspace and/or the stronger the connection, the longer the time in dreamspace will last.
An identical version of these "portal" objects / spots exists in dreamspace, and will bring the person back into the real world, but are incredibly difficult to find. Watchers are physically unable to locate these as they're not supposed to be able to leave dreamspace.