So, about the frog and stone quote, I think it's a reference to one of Aesop's Fables.
Basically, it means that something that is fun for one person may be harmful for another.
https://fablesofaesop.com/the-boys-and-the-frogs.html
So, according to the description, these two might have been husband and wife back on earth?
This could actually be fantastic, but we'll have to wait to see if it even gets scanlated further.