Tensei Shitara Slime Datta Ken: Soukai no Namida-hen

That Time I Got Reincarnated as a Slime the Movie: Tears of the Azure Sea

The second movie in the <i>Tensei Shitara Slime Datta Ken</i> series.<br><br>
After concluding the opening ceremony of the Demon Kingdom Federation Tempest, Rimuru and his companions are invited by the Celestial Emperor Hermesia of the great elven nation – the Magi Dynasty Salion – to visit her private resort island. As the group enjoys their brief vacation, a mysterious woman named Yura appears. A new incident unfolds against the backdrop of the boundless azure sea.<br><br>

(Source: Crunchyroll)<br><br>
<i>Note: Relations are provisional and subject to change.</i>