Jan 9
Speculation: Ground Floor // Utility Room
Mystery alcove/doorway just off the black entryway. My theory is utility/laundry/mud room which makes sense off the main entrance to the house.
I also think we see the reflection of the black entryway in the washer and dryer here:
Finally, it makes sense to have laundry on the same floor as the bedrooms.
(If you custom build an interior and put laundry on a diff floor you're insane and I will not budge on this opinion)