Due to a careless mistake, god of wind Silphyleel unintentionally kills a 28-year-old man named Takumi Kayano. Unfortunately, Silphyleel cannot return Takumi to Earth. Instead, the deity reincarnates Takumi into the fantasy world of Etelldia. Equipped with an assortment of magical powers and bottomless inventory, Takumi spawns in the Forest of Gaia, where high-level monsters roam free. There, he meets five-year-old twins who, despite the dangerous environment, are still alive thanks in part to their extraordinary physical strength. Takumi decides to take them under his wing, naming them Allen and Elena. As the trio embarks on their grand adventure in Etelldia, their very existence may impact the world's destiny.

The duke, full of love and kindness, treads carefully around every living being, be it a tender flower or his seductive maid, Alice Lendrott. Were it not for the devotion Alice shows him and the fondness that grows ever stronger between them, the duke would have barely paid heed to his mother's demand: to either lift the dreadful curse placed upon him or lose his family inheritance. Although the duke has no greed for riches, he yearns to be rid of his frightful powers—which cause all he touches to die—for the sake of those closest to him. As the duke, Alice, and their friends enjoy spirited days filled with the ridiculous affairs of the supernatural, the spring deadline looms heavily over them. Nonetheless, the duke refuses to take any shortcuts in this endeavor if it means betraying the trust of his cherished friends.

Hundreds of years after the large-scale battle against the Nokkers in the city of Renril, the world is unrecognizable. Thanks to the immortal Fushi's efforts in dormancy, he has successfully created a world with modern infrastructure where he and every living species can live in peace. When he finally awakens from his slumber, Fushi is elated to try everything this new world has to offer and revive his friends from the past. While exploring, Fushi runs into Yuuki Aoki, a lively middle school student, who is quick to welcome him and his friends into the house. As the group settles into their new home and learns more about the modern world, Fushi meets Mizuha, Yuuki's friend, who resembles someone familiar to him. It turns out that Mizuha is the descendant of the Guardians: the people whose only goal is to keep Fushi safe. Like her ancestors, she grows fond of Fushi, which brightens up her life. However, as bizarre events occur when Mizuha approaches Fushi, it becomes clear that this new world is far from perfect.

Chika Homura begins her high school career with a goal: to develop a cute girl persona. After quitting the volleyball team despite her all-star status, Chika decides to join her school's underrated Wind Instrument Club and play the flute, believing it to be the most delicate and feminine instrument. For the first time in nine years, Chika reunites with her childhood friend and total opposite, Haruta Kamijou. Unfortunately for Chika, Haruta is not fooled by her efforts to become more endearing. But this does not deter Chika, and she develops a crush on the band instructor, Shinjirou Kusakabe—but so does Haruta! However, Chika's high school life just won't go according to plan, as mysteries begin appearing around her and her friends. The club members must work together to solve the mysteries plaguing the school, all while trying to find more members to compete in musical competitions.