That's like the default for whenever a Japanese girl is photographed. Even if she's been re-programmed for something else, I'm sure sou is going deep enough to hit her factory reset button.
It's true, kids just naturally grow apart. Especially with their age difference. With her keeping an eye on him it seems like they were more than just acquaintances. I think in a future chapter
I am unable to come up with the words to describe how disappointed I would be if that were to happen. I think it would bother me more than when Willow became a lesbian.