That Time I Got Reincarnated As A Slime: Tears Of The Azure Sea

Synopsis

After the grand opening ceremony of the Demon Kingdom Federation Tempest, Rimuru and his companions are invited by Celestial Emperor Elmesia to the Magi Dynasty Salion for a relaxing vacation on a private resort island. However, their tropical escape is short-lived when they encounter a mysterious woman named Yura, a priestess from the undersea nation of Kaien. She reveals that her kingdom, which worships an ancient Aqua Dragon, is facing total annihilation due to a strange pollution infecting the Azure Sea. As a dark conspiracy to awaken a dormant deity surfaces, Rimuru and his loyal executives must dive into the deep ocean to stop an impending invasion of the surface world and uncover the truth behind the corrupted waters.