It's no surprise that Pretty Cure series can get fairly dark. The series that directly preceded this one, Healin' Good Pretty Cure, was actually very heavy in terms of its symbolism and subject matter, so much so that Tropical-Rouge! Pretty Cure at times felt like it was actively distancing itself from its predecessor. But lest we forget, Laura's storyline is linked to Hans Christian Andersen's original literary fairy tale The Little Mermaid, a story where a mermaid's interactions with a witch and humans does not end well for her. (We'll ignore that Andersen maintained that the mermaid's death was a happy ending because she had a chance at a Christian soul.) We've had reminders of that link throughout the series, and they've marked some of the show's best episodes as Laura struggled to distance herself from Andersen's version of mermaid/human relations. But in this final set of episodes, it becomes something that she can't ignore, because she learns a terrible truth when the girls go to Grand Ocean: that mermaids and humans who interact are doomed to have their memories of their time together erased.

That casts a pall over things for the girls, even as they do their level best to ignore it while dealing with the Witch and their own personal hang-ups. Because the sad fact of the matter is that life doesn't stop to let you deal with unhappy revelations—Asuka still has to think about where she's going to high school, Sango and Minori still have a lot of social ghosts to fight, and the Witch is still lurking in the depths of the ocean. Manatsu, thanks to her sunny disposition, has always given the impression that she's not really thinking about the future but instead living in the moment, which makes her breakdown in the final episode—when the possibility of Laura leaving and all of them forgetting her suddenly become real—all the more striking. The other girls have had difficult issues that they couldn't ignore, but Manatsu, it turns out, is a champ at simply pushing those things down until she just can't anymore. Even when she's kidnapped by the Witch's minions, she's able to keep on tropica-shining; it's when the battle's over that she falls apart.

That personality trait speaks to how well-developed each of the girls are. Yes, they can all be slotted neatly into different character types, but over the course of the show they work to rise above them. Laura becomes more empathetic, Asuka learns to admit to what's bothering her, Sango grows more confident, and Minori stops hiding in her own shadow. Their rates of change vary, so they're all still in different emotional places at the end, but it's clear that change has been happening steadily when we see them all living their lives over the credits of the final episode. Whether it was being Pretty Cures, being together, or a combination of both, all five of them are in a better place by the end than they were in the beginning, and that's not always a guarantee, even in a magical girl show.

It's also a journey through which we understand what the villain of the piece underwent in the past, or at least started on. The origin of the Witch of Delays is directly parallel to what Laura must do in the final episode, and naturally it's also tied to the Pretty Cure who came before ours, Cure Oasis. It's certainly worth mentioning that Cure Oasis, who lived at least a hundred years ago, is much more developed than most of the Legendary Pretty Cures in other series; she has a name and a clear backstory that's important to understanding the Witch and the role of our girls. Simply put, the two interacted and liked each other, causing the Witch, at the time known as the Witch of Destruction, to continually delay her showdown with Cure Oasis, which enabled her transformation into the villain Cure Summer and her gang have to fight. The Witch's failure to take any kind of decisive action doomed her, while also making it impossible for Cure Oasis to get any sort of closure herself. That's what Laura needs to avoid in the end; she can't just sit around thinking about whether she wants a life as a mermaid queen or a normal human, because then she'll be no better—or happier—than the Witch.

While this more serious narrative is cushioned by lighter episodes (and one truly weird summoning of Cure Oasis; she's like a shrieking bobblehead from hell), the thread is effectively carried throughout the show's final quarter. And while the finale does its level best to make us worry, there's always a thread of hope: Laura has been shown, time and again, to be actively defying Andersen's narrative of what happens to a mermaid who interacts with humans. If we're going to get a solid happy ending of the sort we're used to, Laura must carry that defiance through to the end, becoming a mermaid who neither lives mute on land nor turns to seafoam. Her growth is shown in how she handles this decision and the ways she finds to circumvent the way that she's been told things “have” to be.

The animation continues to be stronger in this part of the show when compared to the earliest episodes, and there are some interesting design choices made for a few of the characters, such as how Butler finishes up and Cure Oasis' pineapple-meets-Marge-Simpson hairdo. It is of some concern that, as of this writing, the legal stream has not included the baton-pass to the next set of Pretty Cures, although perhaps we shouldn't read too much into that. More important is that Tropical-Rouge! Pretty Cure really pulls through in the final stretch, both thematically and story-wise in the best magical girl tradition.