A pair of mysterious voices lead 14-year-old Ai Ohto to a strange egg, promising her a chance at what she wants most. What's inside the egg? And what does Ai really want?

Ai meets Neiru, another girl who is buying Eggs. She's given the cold shoulder at first, but could that change after the next time they crack their Eggs? Assuming they make it back alive, that is.

While buying Eggs for herself and Neiru, Ai meets Rika, a former idol who is there for the same reason. Rika quickly pushes her way into Ai's life, but what lies beneath her cheerful and callous exterior?

Ai, Neiru, Rika, and Momoe are quickly becoming close friends as they continue to protect Eggs. But as they grow closer, questions pile up and tensions rise.

The girls are attacked by a dangerous new type of enemy while trying to protect their Wonder Eggs. Acca and Ura-Acca may have a solution, but Ai is more concerned with the budding relationship between her mother and Mr. Sasaki.

Ai, Rika, and Neiru confront Acca and Ura-Acca, but are distracted by shocking news from Momoe. Later, Momoe confronts her toughest battle yet while Ai makes a difficult decision.

Friendships are tested as Ai and Neiru realize how much "victory" has cost Rika and Momoe. Ai decides to fight again in spite of what she's learned, but the girl who emerges from her Egg this time may be more than she bargained for.

Ai, Neiru, Rika, and Momoe have all cleared the game, but what awaits them isn't quite what they hoped for. With their long battles behind them, what future will each girl choose?