The simplicity of the relationship is nice, and I like the emotional lopsidedness. Even when the narrator cannot speak with the weight of what he's (she?) heard he still isn't as emotionally low. In my mind I can see this overstuffed sofa, the shape of this girl who, through her body language is just wrecked, and a boy with puppy dog lust lapping it up, but the rest is kind of hazy. I can certainly feel these people, I just can't see them or their surroundings. But that was the immediate goal, and too much more length to the story might have taken away its beautiful snapshot quality, so take it for what it's worth.
Thank you for the comment, and I'm glad my major point made it across! I've been practising showing without telling in my quest to write a decent short story. Scene description has always been my biggest struggle. When is it necessary? What is enough to build the set, but too much that it takes from your imagination? I have read books light on imagery and felt like I couldn't picture it, while others have far too much and become an absolute drag or contain seemingly useless inserts that have no real place in the story. I can paint you a lovely picture of the room they set in, but do you actually care about that?
It's subjective at the end of the day, so I can't say for sure. One thing I noticed in your story was that her eyes were chained to the floor. Without that, the whole scene took place neatly on the couch and that was fine, but since the character now existed outside of the couch I had a notion of a bigger space with no information to fill it in so it was like a white space in the word painting. Some other interaction with the floor, like the guy keeping a foot down because the hard wood grounded him, or the girl's gaze staring far beyond the deep shag, would have built out that part of the scene and filled in the gap. But yeah, that's subjective.