Yggdrasil/Eir
From Create Your Own Story
The Eir are everywhere. Vanaheim could not run without them. They are basically engineers, operating just about every piece of equipment in the ship. They keep the engines running and the lights on, but they also repair damage to the ship, as well as all of it's support craft, and operate the Seidhr, the massive core computer that allows us to analyze vast amounts of data in a fraction of a second. Without the Seidhr we would never be able to make the constant stream of navigational adjustments needed to pilot through the Bifrost System or prevent the energy fluctuations in the engines from causing a catastrophic overload that would kill us all.
In order to do their jobs the Eir have a Neural Interface installed in the base of their skull directly into their cerebellum. It lets them link up with the ship's systems and control them, but while they are linked up they often are completely unaware of their physically surroundings and just stand there like zombies. It's probably too much to pay attention to when you are trying to control a computer with your brain. The ship is built with little alcoves all over the place, especially near important systems, so the the Eir can step out of the way before linking up. As a result they don't get noticed much and despite all they do they aren't appreciated much. After all, no one ever sees them working and even though everyone knows they are the one controlling it, most stuff just gets attributed to "the ship." People say things like, "the ship raised shields just in time!" or "the ship is dimming the lights today to divert power to the engines." Hardly anyone even knows their names, except for the ones on the Seidhr teams, of course.
The Seidhr teams are special. It takes seven people to properly run the thing and since all seven have to be linked up at once they have to be completely compatible with each other. They say the mental link is the most intimate thing a person can experience. Your mind literally has to be connected to another person's. It's very prestigious to be on a Seidhr team and very difficult too. You have to be very good at what you do to even be considered and a lot of great candidates get passed over simply because they aren't able to find a compatible group, but if a person can manage it they are guaranteed to be one of the most well treated people on the ship.
Some people say that the Seidhr teams are really promiscuous with eachother but that is probably just rumors made up by jealous people or troublemakers twisting the intimate nature of the neural link to imply it is sexual. Still... it is a very common rumor so maybe there is some truth to it.