Earth Shopping Channel

Somewhere in the universe today, the music of a shopping channel can be heard. "Earth Shopping Channel" is broadcasting with a bold claim: "We're selling the Earth!"
The hosts are Natsumi, an Earthling, and Kamara, a Martian. The product they'll be auctioning tonight is... the "East Tower"!? What is the purpose of these two, who are selling the Earth without permission and making a profit!?

(Source: Comic Zenon, translated)