[Machine Translation] Rio is a high school girl who was summoned by her sister-in-law as a hero and came to another world. Using the power of "Darkness" that she has obtained, she is now working at her own pace to return to her original world. When Rio hears that her sister-in-law, Amane, is heading to the "Sanctuary of the Wind", which has been invaded by many demons, she is worried and decides to go ahead and exterminate the demons. Rio, who had a hard time in the sanctuary where only wind magic could be used, somehow managed to wipe out all the demons. However, the last "wind spirit beast" that appeared in the sanctuary was ineffective with wind magic, and it asked to be "caught without destroying the nucleus and returned to its normal state. Can Rio successfully conquer the wind sanctuary and protect Amane? The fourth installment of this series unravels the mysteries of the world with a sister-in-law whose conscience is a bit of a mess, and the hard-working Rio who supports her from the shadows!