While living together with his younger sister, Yuki Kinoshita ( 3rd year high school student) transfers to another world in front of his younger sister's eyes.
To rescue her older brother, she pursues after him into the other world by transferring there right before her brother in the nude.
The siblings will have debts in the other world, and start managing the stores together with an elf to repay their debts.
As a kemomimi girl and a young woman join them , both siblings are trying to find the means to return to their original world.
