Written as a software license agreement, the poem starts out sounding like the boring legal text most of us scroll past and click "accept" on. But the terms quickly turn absurd and menacing. You can't act "as if you own your computer," a lost copy costs double, and the company will record your "every twisted fantasy" and sell it to retailers and the FBI. The joke is that the exaggeration doesn't feel far from real life.
The speaker never states an opinion, but the anger is clear in the deadpan tone. Cold, official language is used to describe something invasive, which makes it both funny and unsettling. The mood tightens as the poem goes on: deleting the software doesn't free you, because of the "back door" left behind, and refusing the terms is "already too late." The closing line, "Your bill will be in the mail," is a flat, bureaucratic shrug. It leaves the reader feeling trapped, with no real choice at all.