Miyako Diaries 19: First Priority (Patreon)

That day, Aya and Chihaya set out on their bikes early in the morning. They rode along the main island's western shores and onto Irabu Grand Bridge, pedaling two miles across the ocean - and arriving onto the twin islands of Irabu and Shimoji. Where they were headed, Toori Ponds, were still way on the other side, and it took them a good hour to travel through the island's thick foliages, small villages, and across the western rugged terrains until finally arriving at what looked like a giant basin filled with dark, tranquil water.  Chihaya looked down - and by just  seeing how the surface rippled in the wind, you could tell that the pond was very deep. And sure enough, Chihaya has heard it was 45 meters - and its placid waters housed hundreds of marine life, making it a sanctuary for naturalists and scuba divers.

And yes, Aya also did say it was a sanctuary and seemed very agile and excited, but Chihaya was beginning to wonder if "sanctuary" had some different connotations for her. "Get into these, and do your hair up, Chihaya!" Aya rushed. "These" meant a set of bright orange bikinis, and after Chihaya was done changing, Aya arranged her hair into twin ponytails. Chihaya had no idea what was happening, but being a bit naive and an unsuspecting girl she was, she posed and smiled to Aya's smartphone.

 "Chihaya, we'll dive in now and will compete who can stay underwater longer. Whoever loses has to do this evening's ramen deliveries!" Aya said. Deliveries?? What on earth was she talking about? But Chihaya had no time left to think, as Aya had already grabbed her hand firmly and sprang into air, aiming for the cobalt colored waters far below. Chihaya followed suit and jumped. She didn't mind, the water should be fine and she liked breathholding. But little did she know the next plot that was in place for her - she was to stay down until she blacked out, to be later magically brought back by an obese cat on her belly.

  https://www.youtube.com/watch?v=k-BaWnkk5og