Salaryman Tsuyoshi Mukouda is accidentally summoned as a hero to the Kingdom of Reijseger in another world to help defend against their enemies. Wary of the royal family's true intentions, Mukouda is able to talk his way out of the situation due to his non-combat skill, "Online Supermarket," which is deemed useless. However, this power proves to be anything but useless. With this ability, Mukouda is able to cheaply purchase food products and utensils from Japan—most of which are considered luxuries in this world. As Mukouda cooks up a storm using his ability, he catches the eye of the fearsome mythical wolf Fenrir. The legendary beast swiftly negotiates a contract to become Mukouda's familiar, unable to resist the delicious dishes. With Fenrir by his side, Mukouda travels the world, earning his keep as an adventurer and merchant all the while enjoying delectable meals.

As the first commoner to attend the prestigious Arnold Academy of Sorcery, Ray White is immediately met with contempt from some of the students hailing from nobility. Unbeknownst to them, Ray's real identity is that of the famous Iceblade Sorcerer—a hero who led the country to victory in a past war and is one of the seven strongest sorcerers alive. Despite his legendary status, Ray wants nothing more than to live out the ordinary school life he never had. Ray quickly makes friends with some of the most influential students thanks to his kind and amiable nature. Unfortunately, as those with nefarious motives begin to make their move, Ray may soon have no choice but to use his true power to preserve the bonds that make his new life worthwhile.

Despite standing at the zenith as the strongest exorcist, Haruyoshi Kuga sought even greater power, which led to his demise at the hands of those who envied his might. As he draws his last breath, he casts a spell that allows him to reincarnate and swears to become more cunning, hoping that all his efforts will prove useful in his next life. Haruyoshi is soon reborn in another world as Seika Lamprogue, an illegitimate son of a noble family that prides itself on magic. However, his new family largely ignores him due to his lineage and magic deficiency. Nevertheless, the unbothered Seika leverages the knowledge from his previous life to make numerous valuable allies. As he begins to explore the true limits of his abilities, Seika must also be wary of the consequences that tarnished his past and avoid repeating the same mistakes.

Despite being a handyman with a wide range of skills, Saitou is severely undervalued and underpaid. When he complains, his boss fires him, claiming that he is easily replaceable. As if his luck was not bad enough, a truck suddenly hits and kills Saitou on his way home. Surprisingly enough, Saitou does not die; instead, he is transported to another world. There, he meets a party composed of the female knight Raelza, the moonlight fairy Lafanpan, and the mage Morlock, who are all coincidentally looking to recruit a new member with a skill set like Saitou's. Throughout their time together, Saitou uses his expertise to assist his fellow party members and soon comes to receive the recognition he never thought was possible. However, Saitou's presence may just be the catalyst that will connect a diverse cast of people from different places, slowly uncovering the fate that could bring a great change to this world.