The only compensation for cute Yayaś terminal shyness is the take-no-prisoners vengeance of her alter ego, the raucous Nana. But Yaya doesnt́ even know that her Nana personality exists! Now, just as Yaya and nice-guy Moriyama seem ready to begin a romantic relationship, Shûko, Moriyamaś strong-willed ex, shows up and wants him back. Worse, she captures one of Nanaś rampages on video . . . learning her secret, and revealing it to a very shocked Yaya!