Is it really a straight girl?

Yaki has been kidnapped!
The kidnapper named System was too scary. He sent Miji to work as a maid in a large room shared by nine straight girls, but told her that the other nine were all lesbians.
If she is found to be a straight girl within one month, she will be thrown out as a homeless girl, but after 30 days of normal life, the system will send her back to the original world and give her a big bonus that can't be spent in a lifetime!
When Yaki discovered that the nine girls were beautiful girls of various types, the first day kicked off...