The episode mirrors the first episode but with the roles reversed, as Fuuka now supports a lost Kukuru.

Burned out from her demanding marketing role and constant friction with her boss, Suwa, Kukuru abruptly leaves work without notice. Seeking an escape, she wanders to a remote island where she encounters , Umi-yan’s wife and a research professor specializing in sea turtles. A Return to Roots

Episode 21 of The Aquatope on White Sand (Shiroi Suna no Aquatope), titled focuses on Kukuru’s internal struggle and her eventual path toward healing after being pushed to her breaking point at work. Kukuru’s Breaking Point

The episode ends with Kukuru beginning to regain her spark, setting the stage for her to return to Tingaarla with a renewed perspective. Shiroi Suna no Aquatope - Episode 21 discussion : r/anime

The sight of the baby turtles instinctively rushing toward the ocean serves as a powerful metaphor for Kukuru needing to find her own direction and adapt to her new environment.