You discover how the gate works

As with all things, you aren't sure how long you were asleep for. It will take a while for you to accept the fact that time isn't really a concept here. Happily, you awaken to find the Dungeon Master right where you left him, upright in bed reading a book; or at least pretending to for his own amusement. Unsurprisingly, he did away with the second penis you gave him, but he kept the rest of the appearance you shifted him to. You start to suspect there's more to his heart than he lets on. You have to mind your place, you remind yourself, he is your master, and you are his ****, even if that was a fate that you chose. Your mind dwells on this for a moment, remembering the room you found yourself in that brought you here.

"Good morning Dungeoness" He said warmly without looking away from his book "I take it you had a good rest. You were there for a while."

"I did, yes" You replied "Thank you Master for letting me sleep so long."

"Yes, well, do not get used to it. It's not a thing you or I need anymore. Any moment spent lounging about is a moment you could spend learning and practicing."

"Yes Master," You respond earnestly. You start to recognize his fatherly behaviors towards you. What sounds like scolding is really just him trying to help. Being all alone here for who knows how long, social skills aren't his forte. You sit up in the bed so as to look him eye to eye; the blankets collecting near your ass, the black collar still affixed around your neck, the heavy chain drooping between your engorged tits. "About that, I had a question that I was hoping you could answer"

"There's not been a question you have asked me so far that I have been incapable of answering. What is on your mind?"

"What would have happened had I grabbed any of the other items in that room?"

The Dungeon Masters gaze was still locked on his book "You would have been given your freedom, but you would have lost the chance to see your true potential". While you appreciate the warm compliment, awkward though it may be, it leaves you wanting "Master please!" You try again "Does everything in that room lead somewhere? Do they all go to the same place? How does it work?" There was silence in response, so you try a different tactic. You scoot closer to him and make a pouty face while pressing your tits together and trying to shove them in his face.

"Please Master? Please show me how it works..." The Dungeon Master finally put his book down and looked your curvy, naked body up and down. "You know, you're offering me your body when it's already mine to do with whenever I wish. All you had to do is ask nicely."

Your heart leaps unexpectedly. What had first entered your mind as a casual curiosity quickly grew to a burning desire. "Thank You Master!" You respond gleefully as you hop out of bed. With your newfound power, you imagine a new outfit for yourself, a tight outfit of dark leather that reaches from your **** collar down to your ass, leaving your arms and legs completely exposed. There's a convenient window of cleavage in the center of your outfit, displaying the soft, seductive skin of your large tits, but still holding them inward, keeping your tiny nipples hidden. There were also two tiny holes cut in the bottom, one for each of your holes, just large enough to allow cock. The Dungeon Master returned to his typical unassuming clothes and dark cloak before you moved together to the circular room with a gateway. The room still looks so familiar to you, as it was still very recently that you had been here, but you've gone through so much in such a short time, remembering the first time feels like a different life.

"This room," The Dungeon Master began, his arms open and directed at the far walls "Is an open doorway into The Void, the emptiness between the different planes of existence. It serves as an anchor as well, without it, we would wander aimlessly through the infinite blankness, with no way to reach the material worlds."

"So than, the library, and all other spaces in this pocket universe you created, they must be tied here as well" You surmise

"Very good" He nods gently "You're picking this up quite quickly. Now, take a look at the items along the wall, and look carefully." You do as he suggests, looking over the menagerie of weapons and various odds and ends. They all generally look well made, each seemingly yearning to be held by an able hand. You are sure this is not what the Dungeon Master is getting at. Channeling your second sight, you start to see the threads of fate he showed you before. This is interesting, as you hadn't seen threads stemming from objects before. Each of the objects had two distinct threads.

You relate to the Dungeon Master what you see "The first string is strong and taut. They all look to be leading out through the bars of the gate" you point in the direction, to confirm what you see "There's also a second string, thing and loose in the air. They all look cut and severed"

"They were" He responds in the affirmative "The threads of whoever is brought here are also cut in the same way. When someone picks up any of the items, the two threads will graft together as one," He demonstrates by grasping his arms together with his hands "In this way, whatever they pick up will seem perfectly natural to them. The other string, the one that still is still tied to the world it came from, will lead the person to place and time it was originally taken from."

"Don't they know something is wrong when they go to wherever that string goes?"

"No," The Dungeon Master shakes his head "There may be some initial confusion, but the person will quickly adapt to the world as if that is where they always were. The rest of the world will adapt as well."

"But, how is that possible?" You ask, bewildered "Surely someone would notice if their friend just changed from a human to a halfling, or whatever"

"You forget my dear, that all the strings in the fabric of reality are tied to another. When the graft is complete, the rest of the fabric complies. In your example, the person would be none the wiser, because their friend had always been a halfling, for all intents and purposes."

"I think I understand," you state. Your mind turns inward again "But what about me?"

"What about you? Your story is the same as the others, you just made the decision nobody else did."

"Yes, but there's something else I don't understand." You move close to him "You said that any item the person chooses will seem perfectly natural to them."

"Unequivocally, yes. What are you getting at?"

"I feel hopelessly drawn to you.." your words turn seductive as you press close "the more I stay here, the more unquestionably obedient I become, the more I want to serve and please you. You made it seem like this is just who I am, who I always was. They can't both be true, can they?" You drop to your knees, your face looking up at his, your tits inches from his groin.

"Well, you certainly are proving to be insatiable." He smiles gently as he removes his dick, holding it tightly "You really want this?"

"Yes, Master. May I please have your cock?"

"I can hardly say no when you ask so well" He shoved his dick between the folds of your tits, pressed and held together by your outfit. You moan gently at the sensation as he pushes back and forth, his hands on your shoulders. He is able to keep precise focus of his thoughts, despite the sensation he is feeling.

"Both of these ideas can be true, and in your case are true. Yes, the collar has made you surrender entirely to me, and this relationship has been greatly beneficial to us both, I think" He lets out a small moan as he fucks your tits, something you hadn't seen from him before. "But this is not a far departure from the woman you already were. You chose to put on that collar, after all. Some part of you had to have wanted and preferred submission and domination to freedom. You saw it yourself, when you saw your own self, drawn over a crate. The only thing that is different now, is that you are subservient to me, and I will be a far better Master than any cutthroat vagabond you ever serviced."

"Yes Master!" You acknowledge excitedly. Whether it was the truth in his statements, or just encouraging him to continue fucking your tits was unclear. It didn't really matter. You had no real voice here, only what he allowed you to have. You put your hands against the leather outfit around your chest and move your upper body back and forth, fucking his cock back. His face begins to squirm and contort. You recognize what this is; he's actually going to cum, and not just because he decides to. With a short grunt, he pulls himself away and points his cock at your face, shooting several strings of cum on you. The hot and sticky load is impossibly thick, but you love the sensation. Your eyes closed in reflex, all you hear is his heavy breathing.

"Wipe your eyes my dear, and get up. You're not allowed to clean the rest of that mess off your face until I tell you."

"Yes Master" You say with a heavy moan as you daintily clean the cum off your eyes with your fingers, licking it off with your tongue for him.

"There is no nap for you this time. We have work to do..."