Noir Stardia, lesser son of an even lesser noble, just lost his job. Without a penny to his name, he decides to enroll in the Hero Academy and improve his career prospects. But he'll need to get a lot stronger to pass the entrance exam. So Noir seeks out a hidden dungeon--a legendary labyrinth filled with strange beasts and rare items--where he can train until he's powerful enough to change his fate!

YOU CALL THIS A VACATION?! At the invitation of his brother, who’s studying abroad, Noir heads off to the town of Honest with Emma and Lola. Instead of a relaxing vacation spot, they find a city being attacked by a swarm of monsters! They learn that this “Great Invasion” occurs regularly, and to his surprise, Noir discovers that the person behind this event is someone he knows very well.

At the invitation of his brother, who's studying abroad, Noir heads off to the town of Honest with Emma and Lola. Instead of a relaxing vacation spot, they find a city being attacked by a swarm of monsters! They learn that this "Great Invasion" occurs regularly, and to his surprise, Noir discovers that the person behind this event is someone he knows very well.

After secretly training in a hidden dungeon, Noir Stardia managed to pass the entrance exam for the Hero Academy. Yet despite having inherited powerful skills from a legendary adventurer, Noir's lower social standing means that all of the other students are perfectly content to shun him--all, that is, except for Maria, daughter of a duke. But Maria is afflicted with a curse that will cause her to drop dead the instant she turns sixteen...and her birthday is only a week away. Can Noir use his newly acquired skills to save her?

At long last, Noir has released his master, Olivia, from the Death Chains that kept her bound in the hidden dungeon. But before she'll agree to train him in earnest, he'll have to earn one hundred thousand LP! On top of that, the Hero Academy is about to kick off its annual series of competitions to determine the king and champion of the school. And then there's the new girl in town, Mira Santage, treasure hunter extraordinaire. With all the excitement, Noir's going to have to give his all to prove he's worthy of his master's tutelage.

The school-sponsored King Battle has finally arrived! For one day, the victor will be granted the rights of a king, able to issue any decree they want that the entire student body must obey. Eager to beat Noir, Emma seeks out some extra-special training to improve her chances. However, prepping for the battle soon becomes the least of her worries when buxom treasure hunter Mira arrives on the scene and immediately monopolizes all of Noir's attention! Trouble's on the horizon as Emma and Mira go head-to-head...but who will come out on top?!

At a dance party hosted by Earl Bourne, the mysterious Phantom has kidnapped Emma and made off with the Bourne family jewels! Noir sets off in pursuit along with Leila, who is armed with a Demon Fist attack. Will Noir be able to rescue Emma from this master thief?