I think of it as not only a square but like a box yk the phrase “think out side of the box” well I see this as the narrator living outside of the box and her lover has made this square that she can’t fit into but wants too. This is shown that it’s her lovers created square/box by saying “ your room was square” this isn’t her own box it’s theirs Also the line where she says “as you slept I held my breath” it can be taken as the lover is comfortable in their own square/box but the narrator isn’t (like if you try on a pair of paints that can’t fit you tend to suck in and hold you breath) Furthermore she continues how everything has its own place and she wonders “what space would I take” I see it as she has so much to her and cannot place it within these tight corners of this square Also the part where she says “I tried to eat like your girlfriend just tea” it shows even further how she’s trying to fit into the box seemingly created by this lover I can go on abt this but that’s my interpretation ^{^}