To save elder sister Tome caught by the Hentai space alien of the mystery, Super-heroine, Younger sister Matsu who becomes pink succubus and boarded penideta Sei!

However, there was an appearance of the elder sister who was completely changed by coveting pleasure there.

Though Hentai is voluntarily received, Matsu who traces to elder sisters origin and attaches somehow.

Matsu receives severe pleasure blame by the Hentai further, As the reason is that makes it to pleasant somehow.