In the MMORPG Star Wars: The Old Republic (2011) a new order of Force users was introduced. They first appeared in the expansion pack Knights of the Fallen Empire (2015)
This order was named the Knights of Zakuul and served as protectors of the Emperor of Zakuul, known as Valkorion.
The in-game codex describes them as such:
Before Zakuulans served the Immortal Emperor, they lived in nomadic tribes, each led by three Force sensitives: Matriarch, Champion and High Shaman. After Valkorion had united the tribes, he repurposed these roles to form the Knights of Zakuul. Officially considered protectors of the people, Knights hunt down corruption in the Eternal Empire. In actuality, they are enforcers of the Emperor's will and fanatical in their adoration for Valkorion and his family. Zakuul Knights don't limit themselves to studying one side of the Force, instead teaching balance and exploration. Knights have their own relationships with the Force, but are encouraged to share their findings with the rest of the order. No area is deemed "weak" or "a dangerous path"--they are all parts of a larger, limitless power. Ultimately, every action a Knight takes is to honor the Immortal Emperor. Sacrifices, whether material or a life, are essential to show one's commitment to the Emperor.
This summary of the Knights describes them as balanced Force users, neither fully light, nor fully dark. They seem to be driven only by their desire to serve the royal family.
They are, however, not obsessed with their tasks alone. They do have lives outside of their worksphere.
http://starwars.wikia.com/wiki/Balisk: He has a husband and, if spared by the player, sends a note to thank the player.
http://starwars.wikia.com/wiki/Novo: He is hit hard by the death of his partner and seeks vengeance, but is not consumed by it and is able to overcome it after being spared.
http://starwars.wikia.com/wiki/Senya_Tirall: She makes a clear distinction between her work as a Knight and her social life. She seems to actually consider it a job/career.
"Being a Knight means everything, but I don't let it define me. When it's time to go to work, I'm who I need to be. The rest of the time, I'm just myself."
The Knights of Zakuul seem quite good at maintaining a balance. While playing the game I had the impression to be fighting a loyal police force that was just following orders.
The question: Do the Knights of Zakuul ever fully fall to the Dark Side and why or, if not, why not?