User blog comment:Imouto-tan/Emily Saotome/@comment-4867780-20160713134057/@comment-26362471-20160715031832

It's all completely random so no one knows which is why Shiro likes doing experiments for fun, just to see what will happen.

Yeah, Marie is just a bound to Emily due to having some of Emily's Mana inside of her so not really her biological daughter or anything. Sorry for making it sound so confusing ^ ^;

She did in fact love them dearly and while she did push them to their limits at times she would always reward them, even if they failed :D

Yup no one knows who fathers Emily and her sister, but it is speculated by Isla Ban that their kids might have the same father, but that's just a rumor. XD

It was relatively peaceful besides the monthly test that would push them to use their fullest extent of their powers; their mom even rewarded them even if they did not achieve desired results that was needed. Shiro only let them go because he was also experimenting on Fiora with the Celestial Formula and he was also being betrayed by Kiseki at the time too, so he had a lot on his plate at the time.

He simply lost interest in them after he successfully made Fiora into a super solider and is planning on making more just like her but stronger and mixed with a Demonbane.