The shields are a society founded on the principles of the old Order shieldbearers, their primary purpose is to defend others from harm, even at their own expense. They generally focus on harm-reduction strategies to diminish or distract evil forces, or to redirect suffering to take it upon themselves to spare others.
One of their central features is to use the Praestes ritual to grant psychic defense to their allies or other innocents at the cost of increasing their own vulnerability. Almost all members carry a shield-shaped charm which can be split in two to enact the ritual.
While the shields mostly focus on protecting the innocent and their allies, they are willing to protect even their enemies when the situation calls for it. Be it because it is part of some arrangement for the greater good, or because what they are defending them from would not help. They would not defend a vampire from being killed for instance, but would likely defend him from being tortured if possible, since that does not help anyone and indeed is likely, in their opinion, to drive him further into darkness and depravity. They do not believe in general that an evil person is any less deserving of life or happiness than a good person, but still may support the killing of an evil person if it prevents more evil in the world.
A proudly gender-equal society, shieldmaidens and shieldbrothers of the sentinels are treated exactly the same, and the organization frowns on patronizing attempts to save women from problems they can obviously handle themselves.
Although their mission is to defend others, the shields are none the less a highly pro-active group who are constantly working to capture dangerous individuals and reshape territories through psychic operations and similar endeavors.
While a strongly virtuous group, the Shields do not really believe that it is possible to win the war against darkness. Instead they adopt a harm minimization approach and try to reduce the number of evil acts committed in the world or where that is not possible, redirect evil on themselves or others more able to withstand it.
Territories controlled by The Shields tend to be a lot more peaceful and prosperous, but the evil is still there it is just better hidden and better regulated. With more vampires feeding in nightclubs on supposedly willing fanboys and fangirls than in the streets, more demonborn BDSM clubs or human slaves who sold themselves into slavery in exchange for money for their families instead of being mind controlled into it.
Shieldbrothers and shieldmaidens deployed to controlled territories tend to burn out very quickly when faced with a responsibility to try and absorb as much evil as possible over so large an area.
Initiates are the newer members to the society, they haven't yet received their Praestes charm and are generally testing the waters or being appraised by other others.
Shieldmaidens/Shieldbrothers are the proper members of the society, the shields are a democratic organization with no real hierarchy and all maidens and brothers are considered equal with equal rights.
First Shieldmaiden/shieldbrother, also just called The First, is the name of the leader of a given unit of the shields. While theoretically they have no more authority than any other full member, they're the one who handles administrative issues and decides what to do when the membership is divided or there isnt enough time to vote on an issue.