Two scientists are attempting to distribute the cure for a demon virus that is affecting people all over Japan, however, things have become complicated. One of them has become infected. So begins his battle with himself, as he attempts to not only control his emerging demon side, but also to save the lives of others by wielding its great strength.

Aika's story continues, she is now 19 years-old, 3 years older than in R-16 and 7 younger than in Agent AIKa. Strange phenomena have been occuring at a girls academy. Slowly but persistently the most cute and beautiful girls are joining an internal club, but instead of a sing-in they just get abducted by a strange being that takes control over them by some indecent means. By coincidence Aika was flying-by on her plane when one of this abductions occurred and she was attacked to prevent her from comming closer, but instead of repelling her, she is intrigued about the attack's origin and then the opportunity shows up when her late partners from R-16 decide to investigate those abductions. The story remains full of action and panty flashing that are a must in Aika's series.

A catastrophic earthquake has left Tokyo, and most of the Earth for that matter, under the sea. Aika is a salvager who retrieves various remains from the watery ruins. When Aika accepts the dangerous mission of locating and obtaining the mysterious Lagu, she discovers that she's not the only one after it.

In the first test of a revolutionary personal battle-suit, the MADOX-01, Ace female test-pilot Elle Kusomoto smashes an attacking tank force and humiliates Lt. Kilgore, Japan's most-macho tank-jockey, in the process. Kilgore swears he'll get even, and he gets his chance when the prototype MADOX literally falls off the back of a truck in the middle of Tokyo. Meanwhile, the MADOX, which fell off the back of one truck, off a bridge, and into the back of another truck, has found its way into the hands of college student Koji Sujimoto. Intruiged by the MADOX, Koji makes the big mistake of fooling with it without reading the manual first, and soon finds himself locked in the suit and zooming around downtown Tokyo.