Matsunaga, a salaryman in his twilight years who spends his days going back and forth between Earth and other worlds, and Sena Isezaki, a neighborhood high school girl and former great saint, who secretly has feelings for him. After defeating an earth dragon with his enormous magical power, Matsunaga goes to Carnelia, the capital of Count Karius, and uses the materials to conduct business negotiations...? While enjoying such a fancy otherworldly life, Matsunaga returns to the earth and is contacted by Aihara, a former junior colleague at the company he quit. What was the message? I want you to go out with us. Well, on the premise of marriage. Her bombshell statement leads to a strange incident involving Seina...? And of course, in another world... "Sis, I've missed you so much! She meets Leviria, the daughter of Count Carius, who is also Seina's sister, and goes on a "sightseeing tour of Japan" with her. Can Matsunaga solve the events on earth as well as in other worlds? T