Board Thread:Questions and Answers/@comment-73.195.103.45-20161211025626/@comment-25942629-20161213151444

Mika met people with the seraph gene over seas as well, but it looks like he killed them. If they revive the orphans, Akane or any of the other kids could act as the seventh one, assuming all of them possess that gene. It's possible they were kept for different experiments, too.

It is possible that Michaelas are also seraphs, which would mean that Crowley and Ferid have that trait as well.

I think Tomoe is dead because Yoichi was with her right afterward, and she never came back. Since Lacus is the one who killed her, Ferid might have her as part of his collection. He claims to have the bodies of the other seraph children, too.