Akihiro is a teenaged boy with fantasies. He's about to have date with his girlfriend Miyuki when he finds a strange carpet on his way home. Home, a pretty and over-energetic girl named Malon appears from the carpet. She tells Akihiro about the world of Phantasia and wants to live with Akihiro. But even if Akihiro loves pretty girls, he becomes angry with Malon's magical powers and drives her away. The maniac wizard, Roll, who wants to kill Malon, doesn't help at all.

To save the Earth from alien invaders and their giant monsters, Dr. Kishida does what any other red-blooded mad scientist would do: he builds a giant robot—the ultimate feminine fighting robot! Unfortunately, his grand-daughters refuse to pilot it! Apparently, they've got more important things to do than becoming teenage super-heroes. Besides, how are you supposed to study for your college entrance exams while getting beaten-up in battle? Fortunately for Dr. Kishida, things aren't too well for the invaders, either. According to their reports, the Earth was the perfect target: lush, peaceful, and relatively defenseless. Theoretically, the planet should've surrendered long ago. Now, the war is at a standstill, the dreaded Accounting Department is warning about the serious cost overruns, and the head of the home office has arrived from Galactic Headquarters to personally oversee operations. Has Headquarters decided to unleash, The Audit—or do they have something even more evil in mind? The fate of the world rests upon two people: Aya Kishida, one of the doctor's granddaughters, who may have to give up prep school to pilot the mighty (and lovely) ARIEL; and a mysterious alien named Saber Starblast, who may have the power to defeat the invaders once and for all...

Unaired episodes included with the Blu-ray and DVD release of Nanatsu no Bitoku.

When a strange group of men attempt to kidnap Atsuko Fukune, a dancer at a club, she seeks the help of Mamiya Mugen, a famous detective - who also happens to be a child. When it turns out that other girls have gone missing, Mamiya, with the help of his butler Alucard, springs into action to solve the mystery.