To the shy and reclusive Ryuuto Kashima, associating himself with his popular classmate Runa Shirakawa is nothing but a distant fantasy—or so he thought. After losing a bet with his friends and being coerced into confessing to Runa, Ryuuto's world is flipped upside down: instead of the cruel rejection he was expecting, Runa agrees to go out with him! But dating Runa proves to be overwhelming for Ryuuto, who requests that their relationship remain a secret known only by their closest friends. His decision, however, leads to a series of mishaps that he fears will doom the relationship. As they work through their misunderstandings, Ryuuto reveals his insecurities stemming from his past experiences, and the two grow closer together. Just when things are getting back on track, Ryuuto's middle school crush, Maria Kurose, transfers to his class and begins to stir up a fuss. At the same time, terrible rumors about Runa spread around the school, prompting Ryuuto to take desperate measures to protect her.

Amatsuyu "Jouro" Kisaragi is a completely average second-year high school student who has two dates over one weekend⁠—with the student council president Sakura "Cosmos" Akino on Saturday, then with his childhood friend Aoi "Himawari" Hinata on Sunday. Sadly for Jouro, both girls proclaim their love for his best friend Taiyou "Sun-chan" Ooga, the ace of the baseball team. Accepting each of their requests for advice and guidance, he is now responsible for helping the two girls win the heart of the same guy. Unbeknownst to his friends, Jouro's friendly and obtuse image is all but a ruse designed to cast himself as the clueless protagonist of a textbook romantic comedy. A schemer under his cheery facade, he makes the best of this unexpected turn of events with a new plan: get Sun-chan to fall for either Cosmos or Himawari and take the other as his own prize. But Jouro's last-ditch effort is threatened by the gloomy, four-eyed Sumireko "Pansy" Sanshokuin, who surprises Jouro with not only her knowledge of his secret personality but also a confession to the true self he hid for all this time. Stuck in this hilariously messy situation, each of the five students must navigate countless lies, traps, and misunderstandings to come out on top.

As peace returns to the demon realm, Anos Voldigoad wishes nothing more than to put his reputation as the Demon King of Tyranny to rest and go back to being a misfit at the prestigious Demon King Academy. Unfortunately, any tranquility is fleeting: sinister demons, kings, and deities plot Anos's demise from the shadows. Rumors spread about the "Child of God," a being whose power may rival that of Anos. To uncover the truth and eliminate the potential threat, Anos must journey deep into the land of spirits. However, the spirit world is shrouded in mystery, and it may only be entered after undergoing a series of difficult trials. With unrivaled power and confidence, Anos braces himself to defeat various formidable enemies with grandiose titles. But he—with the assistance of his trusted allies—will barely have to break a sweat as the true Demon King of Tyranny.

Alcia is a world governed by "Count": numbers engraved on a person's body, representing any number related to their life. These Counts determine a person's social status and power in Alcia. If a Count reaches zero, the person is sent to the Abyss, a place rumored to be worse than death. Hina, a traveler whose Count is based on the distance she traveled, witnessed her mother get dragged down into the Abyss. Determined to fulfill her mother's last wishes, she sets off on a journey in search of the legendary Aces—heroes of the war that happened three hundred years ago, bearing a white star next to their Count. While wandering around, Hina encounters Licht Bach, a mysterious masked man with negative Count, and Nana, the owner of a tavern. In the midst of having a good time, Hina is tricked into a battle with a military soldier. However, despite his negative count, Licht rescues Hina and reveals that he has another count, one with a white star, one of a legendary Ace. Plunderer follows the journey of Hina and other inhabitants of Alcia as they discover the truth about their world, the Abyss, and the legendary Aces.