Azuki Yuu

After the death of Saizou, Kabamaru's horribly strict grandfather and iga ninja-sensei (teacher), an old lady Ran Akoko claims that she received a letter from him asking her to take care of his grandson. So Kabamaru runs off with Lady Akoko to the big city Tokyo to gorge himself on yakisoba, Ramen, chow-mein and attend a regular school which turns out to have weird quirks of its own.

Koujirou moves to Tokyo from Japan's northernmost island of Hokkaido and insists on bringing his favourite horse, Hikarikin, with him. The alien king Rel arrives from planet Wedelun and gives him a belt that will allow him to transform into a Miracle Hero and to protect the world from alien menaces. He is more interested, however, in impressing the pretty Yuka, though his rival, Michinari, wants her for himself.