Two images carry this short poem: the sun and the moon. In the first part, the speaker imagines a future where someone looks at them as if they were the sun, the center of that person's world. It's a hopeful wish, but the opening "Maybe" and "one day" show how uncertain and far off it feels.
The second part turns to the present. Until that day comes, the speaker will stay "cool" and "distant" like the moon. The moon is a good choice here: it is quiet and faraway, and it shines only with borrowed light. That may hint that the speaker feels overlooked, or that they are shielding themselves from disappointment by keeping their distance.
The mood is wistful and a little guarded. There's longing underneath, but it is held in check by a calm, almost proud restraint. The title, "Loner III," fits this: the speaker is alone, and seems both wounded by it and determined to carry it with composure.