Meet Eiko 'A-ko' Magami. A sixteen year old student at the Graviton High School for Girls, and the best friend of Shiko 'C-ko' Kotobuki. To her, life is about getting to school on time, doing her homework, and hanging around with C-ko. That is, when she's not trying to survive her awful cooking. Unfortunately, the friendship has attracted the attention of Biko 'B-ko' Daitokuji, a jealous girl who was spoiled by her rich father, and will do anything to eliminate A-ko from the picture, even going as far as to design large mecha units intent on getting rid of A-ko once and for all.
Despite her best efforts, A-ko always triumphed in the end. As a result, B-ko decided to construct a special suit designed to match A-ko's power and settle things in a one-on-one fight to the finish. Unfortunately, their fight was paused when C-ko was kidnapped by aliens who claimed she was their long lost princess. However, they were no match for the two girls who managed to rescue C-ko, albeit with their battle still ongoing. In the end, the craft crashed into a large building, making for a new attraction, and A-ko and C-ko returned to normal school life, while B-ko still remains intent on finishing off A-ko once and for all.