Some (or possibly all) of the Everto were once human.The Everto are Invisible to Normals, as are their vehicles. And all injuries inflicted by their weapons aren't perceived. But even for their inflicted injuries being invisible, it looks like nobody is paying attention to Iris, to the point where it's implied she's literally invisible to them. And while retired resistance fighters seem to be fully visible, the active resistance fighters don't seem to draw in civilian attention, which supports this. If the "Awakened" are invisible to normals even for some of the time, this could mean that their link to the Everto is stronger than it would appear. Not to mention, it'd add yet another layer of hypocrisy to the Everto.
Alexis was born into The Resistance.She seems to act a little...odd...at times, implying she has had very little (if any) contact with the normal human world. She also has studied medicine, which seems a bit odd for someone to do unless she had known about the dangers she will be facing for some time. Furthermore, she is obviously quite experienced, having killed at least one Everto, despite her young age. And to top it all off, it seems as if she treats others (and is treated by others) in Nikki's group like family, implying a long-lasting close connection.