a group in Chicago that is composed of all females that have some degree of magical talent but are not on the tier of a full blown wizard. In book nine, "White night" they are introduced to us as a group of practitioners that are being culled by some one wearing a Grey Warden's cloak. Harry becomes involved because he is the Warden commander for the Eastern United States and The only high profile Grey Cloak warden in the Chicago area. I will leave out who is actually picking them off so that the explanation of this group does not inadvertently act as a partial spoiler In short Ordo Lebes is a Local gathering of minor talented magical practitioners.