Kaitei Sanman Mile  

30, 000 Miles Under the Sea

While returning from an excursion at the ocean, young Isamu encounters the stunning sea-inhabitant known as Angel on a secluded volcanic island. During their encounter, they are ambushed by a dragon that is ablaze with flames. In order to evade danger and escape, Isamu and Angel make use of an observation boat named See Through. Following this harrowing experience, Angel extends an invitation for Isamu to visit her underwater realm known as Atlas.