The Shaderan family has fallen on hard times, and the avaricious and callous baron and baroness will stop at nothing to regain status. They favor their beautiful daughter Anastasia, hoping to marry her into wealth, while they treat the second daughter, Marie, no better than a servant. Years of abuse have convinced Marie that she is truly undeserving of love and attention. On Marie's birthday—used as a ploy to showcase Anastasia—Marie meets Count Kyros Granado, who is immediately charmed by Marie and her knowledge of his culture. Believing Anastasia to be the one he fell for, Kyros proposes via letter. But Anastasia tragically dies on her way to marry him. Forced to take Anastasia's place, Marie becomes Kyros' fiancée, just as he originally intended. Although Marie terribly lacks confidence, Kyros gently helps her find her worth, awakening her to her own beauty and the true meaning of being loved.

Momoko Sakura is an elementary school student who likes popular idol Momoe Yamaguchi and mangas. She is often called Chibi Maruko-chan due to her young age and small size. She lives together with her parents, her grandparents and her elder sister in a little town. In school, she has many friends with whom she studies and plays together everyday, including her close pal, Tama-chan; the student committee members, Maruo-kun and Migiwa-san; and the B-class trio: 'little master' Hanawa-kun, Hamaji-Bu Taro and Sekiguchi-kun. This is a fun-loving and enjoyable anime that portrays the simple things in life. (Source: ANN)

For as long as he can remember, the klutzy Tsuyoshi Yano has been prone to injury. Constantly showing up to school with fresh scrapes and bruises, he has long become accustomed to the pain and to the sight of his face covered in bandages. However, Yano's days begin to change for the better when he is transferred to a new class and meets Kiyoko Yoshida, the class president known for her reliability and kindheartedness. Through Yoshida's efforts to learn more about him, Yano starts to experience the kind of high school life he has always wished for—one filled with laughter and camaraderie. Between casual conversations and countless small accidents, the two gradually grow closer, and their relationship may bloom into something more than just friendship.

Prior to the events of the anime, three factions—the Garan Army, the Kiba Army, and the Aira Army, battle for total dominance of Machine Island. The island is basically a prison, isolated from the rest of the world. The island contains a vast amount of resources, allowing the three factions to create an infinite supply of giant robots for their respective armies. The world government learns that the island's power reactor has become unstable and will explode within 66 hours, destroying all of life and Earth itself. The government sends the Death Caprice squad, composed of mercenaries Ken Kaido and Ryo Magami to solve the issue, along with their giant robot Mazinkaiser, but was that a good idea?