A sick day at home turns into a strange little feast. The speaker is stuck indoors, and even the books, usually a comfort, feel heavy and gloomy. The title, "Feed a fever," echoes the old saying about eating when you're ill, and the poem seems to take that advice in an odd, hungry direction.
Instead of reading, the speaker makes room for "more / leg of pork" and a "roasted head." The images are bodily and a bit grotesque, and they set flesh against the pale world of books. The last line, "setting my paper supper," is where it turns. Judging by the wording, the speaker may be treating the books themselves as the meal, so reading becomes a kind of eating. The mood is restless, dark and wryly funny. It captures the feverish feeling of being fed up with one kind of nourishment and craving something more physical, while the humor keeps it from being purely bleak.