Disclaimer: I don't own the rights to any of these stories.
Martha was hyperventilating, Jack was having flashbacks to the times (plural) he was killed, and The Doctor was just stunned speechless. The rest of dinner passed in a daze for them. After dinner was over, The Doctor snapped out of his weird trancelike state and said, "Follow me." They got as far as the second floor before Professor Yana stepped out in front of them, wand aimed at Jack's face.
Aaand crud, the three thought. Professor Yana said, very quietly, "Follow me. Or else." He then proceeded to grab The Doctor, holding him by the robes and pushing him through abandoned hallways, Martha and Jack following silently. Professor Yana pushed the three of them through a door that had suddenly appeared-"The Room of Requirement", Jack hissed to Martha. Professor Yana gestured to three chairs that had suddenly appeared. "Sit." They sat, still tense.
Professor Yana sat, then sighed. "Don't you dare think I'm here by choice, Doctor. Your fourth self is chasing me around the galaxy right now and a few Daleks are trying to kill me, so I bibliocrisised with a book I found near a supernova. Of course, only after I've done that does your TARDIS tell me that this book is already occupied. She wants us not to kill each other, by the way-that's the only other thing she told me.
"So, you're saying that you have to stay here, and we can't hurt you or kick you out, because otherwise it would basically be crossing my own timeline?" asked The Doctor cautiously. "Yes." "I always wondered why I couldn't find you then," he muttered to himself. "So, we can't give him any advice for later in his life?" asked Jack hopefully. The Doctor looked at him pityingly. "No, sorry Harry." Jack got the message and shut up. The Master turned to Jack, studying him carefully. Then frowned. "Dammit Doctor, I was just going to look at his mind!" "Well, I didn't let you. For the sake of not crossing your own timeline, don't look to closely at my friends. That's all I'm going to say." The Master nodded, looking thoughtful. "Duly noted." The Doctor and The Master then stood up, bowed to each other, then The Master left the Room of Requirement. Martha and Jack were silent, then: "What just happened?"
The Doctor sighed. "We-ell, this is a younger regeneration of The Master-one that a younger me is chasing. He then came across the book we bibliocrisised into and, not knowing about that, bibliocrisised to escape me. We can't do anything about him being here-can you imagine what it would do to our timelines? So," he concluded, "We basically have a truce right now. We leave him alone, he leaves us alone-not because he likes us, but because otherwise it would mess up our futures and pasts." "So, we HAVE to leave him alone, and he HAS to leave us alone?" asked Martha. "Yep!" said The Doctor brightly. Martha and Jack gave sighs of relief. "All of us will get out of here and go our separate ways once the book is over. Speaking of which, do you guys want to see Fluffy on Halloween, or talk to a troll?" Jack facepalmed. "How about no interacting with giant man-eating creatures?" "That's just boring!"
Okay, I know it would be awesome if The Master and The Doctor dueled in the Harry Potter universe, but I just can't make it work. I still have no idea what I'm doing.
:D All you people who review. I love you all.