Bodyguard

A few of the available garrison followers and class order champions have the Bodyguard trait which allows them to join you in your adventures.

You must have a level 2 or better Barracks large building in your garrison. Using your garrison architect table select the Barracks and click the follower slot to get a list of your active followers who have the bodyguard trait. Assign one to the barracks. They will no longer be available for missions.

You must then go to the barracks and locate the follower (usually standing in the entrance) and click them to use the conversation option to request they follow you on your travels. Afterwards they will follow you around much like certain quest NPCs, assisting you in defeating enemies. Bodyguards only accompany you in the outside world. They do not accompany you into dungeons, raids or PvP instances.

As you defeat enemies while accompanied by your garrison follower you gain reputation with that follower and eventually unlock follower-specific special abilities such as a garrison portal or remote follower mission management. The first ability (a combat ability, such as Delvar's Breath of Sindragosa or Vivianne's Meteor) requires at least 10,000/20,000 reputation (Trusted Bodyguard) and level 100, after which you can talk to the bodyguard to complete a quest. The second ability (a non-combat ability, such as Tormmok's repairs, Ishaal's mail or Aeda and Illona's summoning stones) requires 20,000/20,000 reputation points (Personal Wingman) and a quest.

If a garrison bodyguard is defeated, your character get a debuff which prevents that bodyguard from accompanying you for 1 hour (real time), however you can still take another bodyguard with you while you're waiting for the debuff to expire, and defeated bodyguards can still run missions while the debuff is in effect.