Can man lämnar helt enkelt Kingsguard?

Nej, deras löften är löften för livet. De kan inte lämna / gå i pension.

they are sworn to protect their king and the royal family with their own lives, to obey his commands, and to keep his secrets. They are sworn for life and are forbidden from owning land, taking a wife, or fathering children.

- Ett spel av troner, kapitel 6, Catelyn.

Men en person kan inte lämna sig själv. Det var därför de var efter Sandor efter att han lämnade Kingsguard.

Det verkar som om man inte helt enkelt kan lämna Kingsguard, vi får insikt i detta när Joffery Baratheon avfärdar Barristan Selmy.

"You have served the realm long and faithfully, good ser, and every man and woman in the Seven Kingdoms owes you thanks. Yet now I fear your service is at an end. It is the wish of king and council that you lay down your heavy burden."
"My … burden? I fear I … I do not …"
The new-made lord, Janos Slynt, spoke up, his voice heavy and blunt. "Her Grace is trying to tell you that you are relieved as Lord Commander of the Kingsguard."
The tall, white-haired knight seemed to shrink as he stood there, scarcely breathing. "Your Grace," he said at last. "The Kingsguard is a Sworn Brotherhood. Our vows are taken for life. Only death may relieve the Lord Commander of his sacred trust."
"Whose death, Ser Barristan?" The queen's voice was soft as silk, but her words carried the whole length of the hall. "Yours, or your king's?"
"You let my father die," Joffrey said accusingly from atop the Iron Throne. "You're too old to protect anybody."
Sansa watched as the knight peered up at his new king. She had never seen him look his years before, yet now he did. "Your Grace," he said. "I was chosen for the White Swords in my twenty-third year. It was all I had ever dreamed, from the moment I first took sword in hand. I gave up all claim to my ancestral keep. The girl I was to wed married my cousin in my place, I had no need of land or sons, my life would be lived for the realm. Ser Gerold Hightower himself heard my vows … to ward the king with all my strength … to give my blood for his … I fought beside the White Bull and Prince Lewyn of Dorne … beside Ser Arthur Dayne, the Sword of the Morning. Before I served your father, I helped shield King Aerys, and his father Jaehaerys before him … three kings …"
A Game of Thrones, Sansa V

Från detta kan vi anta följande:

• Kungen och / eller det lilla rådet kan befria en medlem av Kingsguard
• Löften tas för livet så bara döden kan lindra dem av plikten
• Löften kan gälla för kungen eller Kingsguard ...
• Löften liknar Nights Watch-löften: Förlora alla anspråk, inga land / fruar / söner, tjäna / skydda riket, slutar på döden, etc.

Så tekniskt kunde man lämna kingsguard men de skulle antingen behöva manipulera kungen eller falla på sitt eget svärd.

Legally? Nej.

Fysiskt? Säker.

While the Hound wasn't kingsquard he is Joffery's personal guard and snaps and leaves. And is pretty good at it until meeting Brienne. And one could use the same loophole Jon Snow used to get out. I'm sure the large army backing him up helped to. But the facts remains. No matter what the laws say if you are powerful enough that no one can challenge you you can to whatever you wan.