The speaker describes a boy who "liked to draw," but the poem quickly shows that "drawing" is a quiet word for self-harm. He works at night, hidden away in the bathroom, and his "gallery" of marks grows in secret. The lines about having "no paper or pen" and needing a bandage "now and again" make the meaning plain without ever stating it outright. The art metaphor softens the subject, but it also shows how private and ongoing the habit is.
The turning point comes by the river, under the stars, when he finally rolls up his sleeves and shows the speaker his scars. His embarrassment, looking down at his shoe, feels small and very human. The speaker answers with a whisper: "I draw too." The ending is the emotional heart of the poem. The mood moves from lonely and secretive to tender and quietly hopeful, because two people who thought they were alone discover they aren't. The simple, rhyming style makes the confession feel honest and unguarded.