Thirty-seven-year-old Satoru Mikami is a typical corporate worker, who is perfectly content with his monotonous lifestyle in Tokyo, other than failing to nail down a girlfriend even once throughout his life. In the midst of a casual encounter with his colleague, he falls victim to a random assailant on the streets and is stabbed. However, while succumbing to his injuries, a peculiar voice echoes in his mind, and recites a bunch of commands which the dying man cannot make sense of. When Satoru regains consciousness, he discovers that he has reincarnated as a goop of slime in an unfamiliar realm. In doing so, he acquires newfound skills—notably, the power to devour anything and mimic its appearance and abilities. He then stumbles upon the sealed Catastrophe-level monster "Storm Dragon" Veldora who had been sealed away for the past 300 years for devastating a town to ashes. Sympathetic to his predicament, Satoru befriends him, promising to assist in destroying the seal. In return, Veldora bestows upon him the name Rimuru Tempest to grant him divine protection. Now, liberated from the mundanities of his past life, Rimuru embarks on a fresh journey with a distinct goal in mind. As he grows accustomed to his new physique, his gooey antics ripple throughout the world, gradually altering his fate. [Written by MAL Rewrite]

Chise Hatori, a 15-year-old Japanese girl, was sold for five million pounds at an auction to a tall masked gentleman. Abandoned at a young age and ridiculed by her peers for her unconventional behavior, she was ready to give herself to any buyer if it meant having a place to go home to. In chains and on her way to an unknown fate, she hears whispers from robed men along her path, gossiping and complaining that such a buyer got his hands on a rare "Sleigh Beggy."

Ignoring the murmurs, the mysterious man leads the girl to a study, where he reveals himself to be Elias Ainsworth—a magus. After a brief confrontation and a bit of teleportation magic, the two open their eyes to Elias' picturesque cottage in rural England. Greeted by fairies and surrounded by weird and wonderful beings upon her arrival, these events mark the beginning of Chise's story as the apprentice and supposed bride of the ancient magus.

[Written by MAL Rewrite]

To the average person, psychic abilities might seem a blessing; for Kusuo Saiki, however, this couldn't be further from the truth. Gifted with a wide assortment of supernatural abilities ranging from telepathy to x-ray vision, he finds this so-called blessing to be nothing but a curse. As all the inconveniences his powers cause constantly pile up, all Kusuo aims for is an ordinary, hassle-free life—a life where ignorance is bliss. Unfortunately, the life of a psychic is far from quiet. Though Kusuo tries to stay out of the spotlight by keeping his powers a secret from his classmates, he ends up inadvertently attracting the attention of many odd characters, such as the empty-headed Riki Nendou and the delusional Shun Kaidou. Forced to deal with the craziness of the people around him, Kusuo comes to learn that the ordinary life he has been striving for is a lot more difficult to achieve than expected. [Written by MAL Rewrite]

The disastrous life of the gifted psychic Kusuo Saiki continues, despite his utmost effort to live an ordinary life. Although he has certainly grown accustomed to dealing with his troublesome friends—who are his biggest hurdle to achieving a peaceful life—he still has a long way to go. Also joining the usual oddballs are a few new faces whose shenanigans add to Saiki's misery, making his dreams of a hassle-free life a distant fantasy. [Written by MAL Rewrite]