Thank you very much! And well seen! It's indeed a curious and funny detail. I tend to be very scrupulous about these myself, and pondered about this very one as I was writing. But in the end I decided to give free rein to the narrative without worrying too much, because in these cases flexibility is always preferable. Nevertheless, in my story, there are other aspects with which I'll need to be stricter.

Anyway, and certainly, a scientist in the midst of a fantasy world could afford to invent units of measurement of the SI of another world. And even if Dave and his scientific ways were not there, the key is that we're in a fantastic world, where everything is possible. I mean, just to cite an example, what reason is there for these people to speak English, when in that world there is not and hasn't ever been a country named England, Anglo-Saxon culture, or anything of the sort? That's precisely why I love to tell stories in an isekai, because there, you have the freedom to introduce the elements you want almost by definition!

Hope you've enjoyed what's available. Right now I'm busy with my other game, but sooner or later I'll resume writing chapter 6 of Monster Girls: the Advent (in Spanish), and the translation of chapter 5.

See you around!