An animated flash series of the manga Mini Vanguard.

On a sunny day, Mihoshi Kuramitsu decides to take a peaceful nap while everyone else does chores. Sick of Mihoshi's laziness, Aeka Jurai Masaki questions her capability as a Galaxy Police Officer. Her pride wounded, Mihoshi decides to prove that she is a skilled first class detective by telling the story of how she and her partner, Kiyone Makibi, put a stop to a series of thefts involving Ultra Energy Matter. To make it more fun, Mihoshi inserts Tenchi Masaki and the others into her story. However, her fantastical tale may just demonstrate her lack of a grip on reality rather than showcase her accomplishment as a talented officer.

In this magical world, one is easily identified as having magical abilities by a distinctive mark on their face. Those unable to practice magic are swiftly exterminated to maintain the magical integrity of society. However, deep within a forest lies an anomaly in Mash Burnedead, who can be found pumping iron with one arm and lifting a cream puff with the other. This aloof boy with superhuman strength—but no magical abilities—leads a quiet life with his father, far removed from society. Mash's peace is soon disturbed when the authorities discover his lack of magical powers. They issue him an ultimatum: compete to become a "Divine Visionary," which would force everyone to accept him, or be persecuted forever. To protect his family, he enrolls in the prestigious Easton Magic Academy, which only the most elite and gifted students are allowed to attend. Now, Mash must overcome his shortcomings as a magicless being and surpass the other students—relying solely on his muscles.

Far to the north of the world lies Hell's Gate, a portal formerly used by the Demon Lord to invade the human realm. Thanks to the legendary hero Shion Bladearts, wielder of Excalibur, and his loyal band of companions, the Gate was sealed off and the demonic threat was vanquished. Unfortunately, the seal was incomplete and has begun to weaken, allowing the demons to once again begin their attack. Worried about the safety of his village, selfish and perverted farmer Touka Scott dig pitfalls to defend against the demons. But fear not, for Shion is on his way to reseal Hell's Gate and save humanity! Or at least he was, because the legendary hero is dead, having fallen into one of the pitfalls Touka dug. Luckily, dealing with the dead is the specialty of necromancer Anri Haynesworth. While she can't revive him, Anri can at least salvage their quest by forcing Touka's soul into Shion's rotting body and dragging him along to Hell's Gate in Shion's place. Not wanting to be left behind, Touka's childhood friend Yuna Yunis tags along. Together, the three of them set out as what just might be the most unsuitable party to ever try to save the world!