The speaker describes their own shadow as a constant companion: it walks behind them, listens when they talk, and copies their height and size without ever saying a word. The short, one-word lines, many ending in "-ing" verbs, make the poem feel like footsteps, steady and repetitive, much like the shadow itself.
The mood shifts as it goes on. At first the shadow seems gentle, almost comforting, a silent listener. But then it is "crying" and "despairing," as if it carries the speaker's sadness, and it vanishes at night, when the speaker may need company most. By the end it is both "twin" and "stalker," an ally and something unsettling. The final lines suggest the speaker feels abandoned in their heart, left with only a shadow of connection. The poem seems to be about loneliness: being accompanied, yet not truly understood or kept company.