Actual dialogue as Yorino is the love child of two women. Yorino's other mother(unintentional rhyming) explained that a Mure's body is composed of high-density aegis energy. When a Mure falls in love with a human who also can use aegis, and meld their astral bodies, (i.e. sex) although the chances are low, the female Mure will take in the aegis energy from her lover and becomes pregnant with another pure-blooded Mure. And since Yorino's mom was a Mure, and her other mom was a bastioner, tYorino was the product of that union. There's no futa involved. Thus making Yorino a science baby