@feratul Here are my thoughts from least likely to most, though I am going back and forth on my top three most likely/thinking about some combination of them:
I agree, suicide seems the most unlikely. Nor do I see her getting hooked by a fisherman and getting eaten. The only possibility I can see for this route is that there's some sort of underwater conflict in the final volume and she dies from an injury.
1. She recovers her sanity
Also agree, the chances do seem very slim. While a part of me holds out some hope that she gets a good ending, she is probably past the point of no return. And if she does recover, it would seem like a bit of a cop out.
2. She vows to stop eating her friends but kills her emotions in order to survive/rule over her kingdom
"Worst possible ending" sounds about right. Would be very sad. And she seems unable to rein in her impulses, so unlikely but still possible.
3. She runs swims away far from anyone she knows, alone but never hungry
Whether it's a self-exile or if the kingdom catches her and exiles her (though jail would be more likely?), it would also be a sad ending. Wouldn't get to see her friends ever again, but at least she's not eating them. Or maybe marries into another kingdom, where eating seafood is acceptable...
4. The Silence of the Fishes/Atlantisian Genocide
Wow, dark route ending now huh. Though, I wouldn't surprise if the author chooses this ending because of the unpredictable outcome of every chapter.
Somewhat logical route, would be a nice horror "twist" ending given that she still retains her "
humermanity" for now and story makes it seem like there's still some hope. "Silence" ending would mean she actively either hunts and/or cooks her friends. "Genocide" ending is if she's driven to madness. Possibly even conquering other kingdoms for more food. On a related note, what if there's some dark royalty history of eating fishes / enemies? 🤨
Yeah, that's what I meant, that she can live on the surface like a human if need be. She might still eat fish though (overlap with self-exile route), or she could give up seafood (as penance). But would her family force her to come back to rule the kingdom?
I think she will keep eating seafood regardless, it's just a matter of can she get away with it and how she handles her guilt.