Can't imagine; post some photos of the entire space.

Pictures will certainly help but I would look into opening it up and put railing instead of it being walled in.

Sorry, see I’m terrible at this stuff.

I am still confused I see the stairs going down , usually this type of box is to allow head room for a staircase but not usually this huge for that purpose. Can you open it up and just see what is there and takes pics of the whole staircase that this is above. If it has to stay use it like place for a set of shelves for a library type look and forget it.

Exactly it is used for head space in the stairway. I don’t know why it is big as it is. The prior owner built the house in 1993 and as we take each new project we find all kinds of things and say”why?, what were they thinking?”

Do you need access to the opening above the box? if not, i would create a set of storage shelves that go all the way to the right wall and to the ceiling, then the box just disappears into the unit - this is ugly but just trying to communicate what I mean 😅

I need access that is the only point where I can access under the roof. One other tidbit. This room will be full on Midcentury Modern. Orange carpet, green walls, 50’s and 60’s wall art. 50’s and 60’s furniture. So this giant cube needs to fit in.

I think making it disappear into the background makes the most sense, however you want to do that - I would not think of it as an architectural or design element

If you are going full on 50’s/60’s vibe I’d say to wallpaper it and the back wall (something bold). A thin piece of clear glass on the top will protect the wallpaper.