The speaker stands in a gay bar and sees it as the bottom of a pool where he has already drowned. The setting is a place of nightlife and company, but the image turns it into something airless and submerged, as if he is looking up at a life he can no longer reach. The title and the opening line together suggest a person who feels the bar has swallowed him.
The second line brings in mirrors, and the third makes the point painfully clear: the "bloated shape" shifting in the glass is him. "Bloated" is an ugly word, the kind used for a drowned body, so he sees himself as something dead, swollen and distorted. The tone is bleak, self-disgusted and strangely calm, with no cry for help, just a flat recognition. The poem's brevity adds to this. It feels like a glance in a mirror that he cannot look away from, and the mood is one of shame, exhaustion and grim honesty.