Airi loved Reina, but she is a shy girl and couldn't find a courage to declare it.
So she was happy when Reina talked to her and kissed her.
However, Reina turned out to be a girl of a sadistic nature. Trying not to be dumped, Airi sweared that she would be a slave to her beloved one and do anything for her.
Reina's order were very hard ones: Airi had to expose her body in public all the time.
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