Tensei shitara Slime Datta Ken  

That Time I Got Reincarnated as a Slime, Regarding Reincarnated to Slime, Re: My Reincarnation as a Slime, TenSura, 転生したらスライムだった件, Regarding Reincarnating as Slime, Odrodzony jako galareta

On this typical day in Tokyo, Satoru Mikami finds himself in conversation with his colleagues when he gets attacked by a thief who stabs him. Despite being 37 years old and working for an average corporate job, Satoru regrets that he will die a virgin. Suddenly, after fading out, he wakes up to the sound of a mysterious AI voice giving commands. To his surprise, he finds himself in a strange cave with a new body made of slime. With this new form, he gains the ability to absorb anything and take on its appearance and abilities. While exploring the cave, Satoru encounters a massive dragon named Veldora who has been sealed away for centuries. After befriending the creature, Rimuru Tempest is bestowed upon him as his new name. Determined to change his fate and that of his new world, Rimuru sets out on a grand quest.

Tensei shitara Slime Datta Ken has been published in English as That Time I Got Reincarnated as a Slime by Kodansha Comics USA since August 22, 2017.