Many years have passed since humanity disappeared from Earth. At the Galaxy Tower hotel in Ginza, Tokyo, the capital of Japan, the hotelier robot Yachiyo and the employee robots are waiting for the owner to return and the time to welcome human guests again. However... the first guests to arrive in 100 years are extraterrestrials. As they arrive one after another, are their purposes to stay, invade, or perhaps neither...? The hospitality of Yachiyo and the robots, with the prestige of Galaxy Tower on the line, begins now.

(Source: Takeshobo, translated)