A locked transfer dependency between a channel and Donor of the same gender. Digen and Im'ran were in an Orhuen relationship. A selyur nager locked transfer dependency between two matchmates of the same sex.
Dependency of the Lortuen, Torluen or Orhuen type can be a terrible risk because if one of the pair dies, the other is very likely to follow in a short time. For a very long time, such dependency relationships were considered the stuff of myth because they happened so rarely, and very few of those instances were ever reliably documented. Once civilization stabilized and record keeping became reliable, the myth became a reality -- but never a common one.