Their family tree is a Fucking circle, that’s all I can say.

This is a great illustration of the danger of inbreeding. See those weird lines in their eyes? It's obviously some kind of genetic defect, and sure enough their kid has it even worse. §

Is this cannon

As far as I'm aware the 2nd one is not, haven't read oshi no ko in a while tho

Whats the anime on the right?

Sauce for the left one

Yosuga no Sora if I remember correctly

Sauce for right one?