Cain heads to the royal capital with his family for a party celebrating his debut in noble society. On the way, they see a carriage being attacked by monsters, and Cain runs to help... and then learns that he's saved the princess and the duke's daughter.

Cain has been named a baron and given a mansion—an old, dilapidated one. But with his magic, he's able to fix it up like new in no time, and he immediately starts preparing to host a debut party to introduce his mansion to noble society.