Ghost took a step backward in surprise at being addressed, running into Nihilego's body as she did so. "U-um, we're just... ordinary, um, travelers." she stammered, "Don't mind us, w-we'll just be on our way."
"Ni, ni." Nihilego said quietly, tapping her arm with a tentacle. Ghost looked down and realized she'd become invisible. Dang - why did that always happen at the worst times? But the fact that no one had seized her or Nihilego yet was a good sign.
"...Okay, I guess I should probably tell you the truth, then." said Ghost, summoning all her willpower to stay visible despite her nervousness, "Nihilego and I are from another dimension. We came through something called an Ultra Wormhole. They can be opened by a very few Pokemon. Nihilego and I were actually part of an experiment to create other Pokemon, and even humans, who are capable of opening these Ultra Wormholes to travel among dimensions. Nihilego was a success, although it has very limited use of the ability. It created an Ultra Wormhole to get us out of there, and that took quite a toll on its energy. Nihilego and I actually share some of the same DNA because of the experiments - that's why we have such an intimate bond. As for me, I was less of a success. I can pass through matter, but not between dimensions. And, of course, I can become invisible." She paused, only then realizing that she hadn't yet properly introduced herself. "Um, this is Nihilego." she said, stroking one of its tentacles, "As for me, I guess you can call me Ghost... though I guess my real name is 'Subject 5542.'"
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Yet in my new wildness and freedom I almost welcome the bitterness of alienage. For although nepenthe has calmed me, I know always that I am an outsider; a stranger in this century and among those who are still men.
-H. P. Lovecraft, "The Outsider"