Nikky's "Lingering" is about the way a person can stay with you after they're gone, or after something between you has ended. The poem never says who "he" is or what happened, but the speaker clearly can't get away from him. Everything in her day seems to carry a trace of him: her hair, her sheets, even the headphones she puts on to escape into music.
The details get more intimate and more personal as the poem goes on. Hair and sheets belong to private, close moments, and then the songs suggest that even her escape routes are taken over. Every track becomes a reminder.
The mood is quiet, restless, and a little haunted. The speaker doesn't shout or accuse. She just keeps repeating "he's here," which makes the feeling sound worn down and inescapable. The last line, "always just lingering," leaves us with a sense of longing mixed with exhaustion. We can't tell whether she wants him to leave or secretly wants him to stay.