Double Reaction! Plus

Yuri is a passionate yaoi fangirl who is deeply annoyed that her twin brother Kairi is more attractive than she is. The two stumble onto a wishing stone. Yuri picks it up and wishes to become a "sexy beast" — then drops it and breaks it. Eighteen days later, on the first day of a new school year, the broken stone reappears on her bed. When Yuri touches it, she and Kairi swap bodies. Kairi is unhappy about this. Yuri, now inhabiting a bishounen body, is delighted. The switching proves to be unpredictable, and the twins' new life begins.