This is debatable. To my understanding "isekai" means "gone to another world". While in Japanese media often portrayed as reincarnation, afterlife, or summoning, to my understanding it isn't limited to those alone and shipwrecked should count too.
You have a point, since the story and style straddles both genres.
As many a librarian has wailed: "If writers would only keep to the Dewey Decimal System!!"
Given the story so far , it would entirely depend on whether that lovely mystery lady is of natural (scientific) or supernatural origin. Since proper Isekai always has a supernatural component to it.
If my hunch is right, the story would be S-F, but since I don't read LN/WN and can't read moonrunes to save my life, I'll be dependent on our dear scanlators to see if I'm right or not.
Visualisation don't match this. "Boob/bikini armor" is a major detriment, even if it is on top of other clothing.
points at illustrations in SF/Fantasy since A.C.Doyle/Verne throughout the first and second feminist waves up to modern chick-lit
Ith Thradithion. Silly, but still Thradithion.. Male fantasy armor is just as insanely impractical.
And really.. There's a host of girls, even trained combatants, that
like to prance around in that stuff. Makes boys need a chiropractor... And even though I'm getting on in age.. I ain't complaining. Makes for a nice show, including the devious grins of the ladies when one of the ..less experienced.. lads forgets to look where he walks...
And in the end.. This is Entertainment, not a historical academic treatise.
