Season 1

Satoru Mikami is a typical corporate worker, who is perfectly content with his monotonous lifestyle. One day, 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 which the dying man cannot make sense of. He regains consciousness only to discovers that he has reincarnated as a slime in another world. He has also acquired newfound skills—the power to devour anything and mimic its appearance and abilities. He then stumbles upon the Catastrophe-level monster "Storm Dragon" Veldora who had been sealed away for many years. 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 his past life, Rimuru embarks on a new 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.

Satoru Mikami es un trabajador corporativo típico, que está perfectamente contento con su monótono estilo de vida. Un día, es víctima de un asaltante al azar en las calles y es apuñalado. Sin embargo, mientras sucumbe a sus heridas, una voz peculiar resuena en su mente que el moribundo no puede entender. Recupera la conciencia solo para descubrir que se ha reencarnado como limo en otro mundo. También ha adquirido nuevas habilidades: el poder de devorar cualquier cosa e imitar su apariencia y habilidades. Luego se topa con el monstruo de nivel Catástrofe 'Storm Dragon' Veldora que había estado sellado durante muchos años. Satoru se hace amigo de él y le promete ayudarlo a destruir el sello. A cambio, Veldora le otorga el nombre Rimuru Tempest para otorgarle protección divina. Ahora, liberado de su vida pasada, Rimuru se embarca en un nuevo viaje con un objetivo distinto en mente.