The story is set in modern times, but the twist to the story is that Mazinger is an ancient weapon of the gods, left on earth to battle the evil space gods who have returned to take over the universe.

It all starts when Gokudou steals a pouch from a fortuneteller, thinking that it contains a gem. Instead, it turns out to be a rock, from which emerges Djinn. The genie grants Gokudou the standard three wishes, but our anti-hero doesn't think heavily about his wishes. Gokudou does get his wishes, though not exactly in the fashion that he expected. The best thing he gets out of his wishes is Honou no Maken, a magical sword that enables its owner to do fire attacks and it can be summoned from anywhere in the world. Even with an enchanted sword, Gokudou doesn't get much respect. He gets turned into a woman by Djinn, who is also a shapeshifter. He is followed by Rubette La Late, a potential love interest who is more interested in adventure, karaoke and outperforming Gokudou. He gets whapped on the head a lot, especially by the fortuneteller who reappears throughout the series just to plague Gokudou it seems. Later in the series, he gets another sidekick, a former evil magician named Prince, who is more handsome and a better womanizer than Gokudou. (Source: AnimeNfo)

Shungo Ninomiya is just an ordinary, run-of-the-mill high school student who lives at home with his older sister Ryoko—at least when she's not away doing her job as a mercenary. However, Shungo's life ceases to be normal the moment a cute girl named Mayu Tsukimura descends into the middle of his school's campus in a military-grade helicopter. It turns out Ryoko sent this girl, along with her older brother Mikihiro, to live at the Ninomiya household. But the newly-arrived siblings are a little special: Mayu is, in fact, a succubus and her brother, an incubus! And as if the circumstances are not problematic enough, Mayu is crippled with androphobia—the fear of men—and it's up to Shungo to help her overcome this at the behest of his sister. Ryoko plans to force Mayu to be closer to Shungo, and to do this, she’ll employ some questionable methods such as having them share the same bed and even take baths together. The situation further complicates when student council president Reika Houjou arrives as the new maid of the Ninomiya family, and she will stop at nothing to thwart Shungo and Mayu’s sexually-geared training. With the sudden arrival of all these oddities, Shungo's ordinary life is about to be thrown into utter turmoil. [Written by MAL Rewrite]

Long ago, magic was abundant and enriched the lives of all people until its usage in war. To end the chaos, seven of the most powerful mages gave up their lives in order to seal all magic. Now, almost one thousand years later, their magic seal Magiaconatus hosts Granbelm, a monthly series of battles meant to determine who among its participants is worthy of the title of Princeps, the one true mage. On the night of a full moon, high school student Mangetsu Kohinata is suddenly transported to an illusionary world where six mages are participating in Granbelm. Mistaken for an enemy mage, Mangetsu is attacked by two mages until she is rescued by Shingetsu Ernesta Fukami and her Armanox Viola Katze. However, when Shingetsu is ambushed for protecting her, Magiaconatus grants Mangetsu the Armanox White Lily, allowing her to fight off Shingetsu's assailant. Overwhelmed by the revelations presented to her, Mangetsu decides to help her new friend fight in Granbelm and make her wish come true. [Written by MAL Rewrite]