Oz and Gil - "Three things"
Once upon a time, Oz turned fifteen and the world turned on its head. His coming-of-age ceremony had Oz stabbed, then him nearly killing his best friend Gilbert and flung into the Abyss by a shadowy group known as the Baskervilles. Trapped there, Oz did the only thing to get out; forge a contract with Alice, the Bea Rabbit (The Black Rabbit) and open the Way back into the Real World, only to realize they had timeskipped ten years.
1. The Servant
Gil is always first and always, Oz's servant.
Which means two things for Oz. Mostly it means that no matter what happens, Oz can count on Gil to follow his orders and listen to him. Oz doesn't abuse the title of Master over Gil, but he recognizes that Gil wants, no, needs to have a Master to serve. It's one of the things Oz realizes early on in life when Gil insists to protect him no matter what. It's also a way of keeping Gil in check in case he does something foolish like attacking people for the sake of a hat or getting his co-operation when Alice is concerned.
Secondly and more importantly, is that Oz considers him Gil's master. That means that Oz is completely and utterly responsible for Gil's actions and his well-being.
Page 57 (of Volume Two)
Tiny!Gil: Ah...
No...
You can't... protect me...
Because...
Protecting "Master", is my job----!!
PG. 58
tiny!Gil: Ugh
tiny!Oz: What master... (I have no idea what you're talking about)
Just now, I wanted to say, you've already become my servant,
and that means, From now on no matter what happens, I will protect you!
Because that's "what a master should do"! (heh heh)
To Oz, this is the most important fact to their relationship. Not that Gilbert is a servant, but Oz is his master and Oz needs to fulfill the duties of a master by protecting Gil, no matter what.
In camp, they also stick with the titles "Master" and "Servant" not because they're ashamed of being friends or because they have anything to hide, it simply defines their roles of what they are. It's something Oz carries with pride; the fact that he and he alone is Gil's Master.
2. The Friend
Oz - You won't be doing it as a servant, you're doing it as a friend.
It's quite clear, for these two, that they're more than just master and servant. Gil is the person that Oz confides in the most.
If Oz has a problem, the first thing he would do is go to Gil. If Oz is feeling sad, Oz would go to Gil. If Oz is angry and needs to vent, he would go to Gil because he knows Gil listens as a friend, on the same level as him who understands him more clearly than any other person would (barring, say, Alice, who knows what Oz is like on a more instinctive level). Oz is aware that when Gil gives him advice, he's only thinking of Oz and only Oz's wellbeing first and in the back of his mind, this pleases Oz.
Gil is also the only person who knows what Oz is like and what Oz has been through. There are no secrets between Oz and Gil. Though, quite often, when something is troubling Oz, Gil won't press the issue and Oz appreciates that, but at the same time, Oz knows that he needs to come back to it later because it'll bother Gil and that's something Oz wants to avoid the most. More than anything, Oz doesn't want Gil to worry for his sake.
3. The "Precious Thing"
Oz - To me, that person is my friend, my most precious thing.
If Gil died, Oz would die.
Maybe if Alice was there too, Oz would live long enough for her, but if there was no Alice and Gil died, Oz would die. That's how important they are to each other. Oz needs Gil to support, to be there for him. Gil remains to be his only link to the happier days of his childhood not to mention, his only friend in his entire life. Also, Gil supplied the most important promise to Oz, the promise that Oz clings onto.
The promise of "always".
Gil will always be Oz's servant. Gil will always be there, Gil will never betray him....That was the promise Gil gave Oz when Oz returned home after his kidnapping.
PG. 78
Oz: a normal, peaceful life will always have a day when it gets destroyed, right?
So no matter what happens, even if it's being betrayed by someone, I'll just accept reality...that's all.
Gil: .....
...yes, nobody knows what will happen tomorrow...
--But, Young Master.
PG. 79
No matter what happens, I will always be by your side.
I...know of the darkness in your heart.
And you, also know of my weaknesses...
That...which ties us together is not light, but the shadowed parts.
Therefore...from today on, no matter how long, even if our positions in life change--
PG. 80
Gil: I want to... always be your servant.
Oz: ----
I...don't believe in "always"...
Gil: hehe... I know, but...
PG. 81
Gil: Don't you think believing in it once isn't too bad?
I will never betray you, and never to let you get hurt, because you are--...
my...
master.....
Oz never showed it, but he put all his hopes on that promise, on the one thing that he prayed would stay eternal in his life. Even ten years later, when Gil is lamenting the change in his own identity and being one of the Nightlays, Oz completely dismisses it because Gil had still been fulfilling his promise to stay by Oz's side and doing all he could to protect Oz even when Oz was trapped in the Abyss.
When Gil was mind-controlled by Doldon and ready to shoot, Oz adjusts the revolver so that it fit under his neck and said, "You hate me, don't you...? Because of me... you nearly died. Even though...I really wanted to believe in your "always"...If, because of me, that "always" will become a "falsehood", then rather than seeing that moment--...it'd be better if I just died here."
Oz considers that "always" to be a part of who Gil and he is together and if that was ever broken, Oz would completely lose faith in everything he ever had faith in to begin with. That is how important Gil's very existence is to Oz and that is why Oz places Gil as the most important thing in his life and one he will never give up without a fight.
tl;dr version
-Hurt Gil and Oz will cut you.
-Gil is v. important to Oz
-We're not gay (rly)