Koichi is convinced he'll never manage to become a hero, until he meets someone with an odd take on justice.

Now that the school's marriage training course has started, Jiro and Watanabe, who don't get along, become a couple. They decide to get along to reach A rank and change their couples.

After surviving an attack from the rival Kouga clan, Ittoki Sakuraba, an ordinary boy, discovers that he is the 19th heir of the Iga ninja. Ittoki learns to become an Iga clan ninja and joins the war between the Iga and Kouga clans.

Shikimori parece ser a namorada perfeita: fofa, divertida de se estar por perto, doce quando ela quer, mas ela tem um lado sombrio legal que aparece nas circunstâncias certas.

Aos olhos do público, os líderes do heroico Gelato 5 e da organização vilã Gecko são inimigos jurados. Na verdade, eles estão perseguindo um romance proibido.